Believes That He Alone

by WinterSky101

When Harry and Dumbledore arrive at the cave that houses Voldemort's Horcrux, they find they're not the only people there. Half-Blood Prince AU.

"I can only conclude that this potion is supposed to be drunk."

"What?" said Harry. "No!"

"Yes, I think so: Only by drinking it can I empty the basin and see what lies in its depths."

"But what if - what if it kills you?"

"Oh, I doubt it would work like that," said Dumbledore easily. "Lord Voldemort would not want to kill the person who reached this island."

Harry couldn't believe it. Was this more of Dumbledore's insane determination to see good in everyone?

"Sir," said Harry, trying to keep his voice reasonable, "sir, this is Voldemort we're-"

"I'm sorry, Harry; I should have said, he would not want to immediately kill the person who reached this island," Dumbledore corrected himself. "He would want to keep them alive long enough to find out how they managed to penetrate so far through his defenses and, most importantly of all, why they were so intent upon emptying the basin. Do not forget that Lord Voldemort believes that he alone knows about his Horcruxes."

Harry Potter and the Half-Blood Prince, Chapter Twenty-Six: The Cave

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The cave was so dark that even the beams of light from Harry's wand could only illuminate a few feet in front of him. The only other light came from the greenish basin set in the middle of the island, so of course that was what Harry and Dumbledore approached once they stepped out of the boat.

It was only when they reached it that they saw the body crumpled at its base.

Harry stared at Dumbledore with wide eyes and was gratified to see that Dumbledore too looked startled by the development. "Do you think it's another one of the bodies, like in the lake?" he asked after a moment of silence. "Do you think it's here to stop us from getting the Horcrux?"

"It could be," Dumbledore replied, "but I believe there may be something more at play here."

Before Harry could stop him, Dumbledore knelt next to the body and flipped it over. Harry hissed in a sharp breath as he saw the person's face, framed by long dark hair. "Sir, is that- He looks like Sirius!"

"Indeed," Dumbledore replied, a frown furrowing his brow. "But I do not believe this is his body."

One second glance, Harry agreed; the body was younger than he'd ever seen Sirius in life, closer to his own age. The person was also a bit smaller and slighter than Sirius, even than the young Sirius Harry had caught glimpses of in Snape's memories the year before. It had to be someone else, then, but someone who looked very much like Sirius.

"Do you know who this is, Harry?" Dumbledore asked, looking up at him.

"No," Harry admitted. "But he does look like Sirius. Do you think they're related?"

"If my theory is correct, then yes, they are related. I believe this man is Regulus Black, Sirius's younger brother. And I believe he is alive."

Harry gaped at Dumbledore. "But-" There were too many protests in Harry's mind for him to pick one, so he settled with, "Sir, how?"

"I do not know," Dumbledore replied, looking back down at the body. "Did Sirius ever tell you about his brother?"

"He said that his brother was a Death Eater," Harry said. "And that he died a long time ago. Professor, how could this be Regulus Black? He was only a little younger than Sirius, wasn't he? And he's been dead for longer than I've been alive!"

"Regulus Black was about a year younger than his brother," Dumbledore agreed. "And he was believed to have died nearly two decades ago. But if this young man is not Regulus, he is a very convincing doppelgänger. I knew Regulus when he was at Hogwarts. Not well, but enough to recognize him. This is the body of Regulus Black, and it is alive."

"But sir, that's impossible!"

"Ah, Harry, with magic, there are many impossibilities that may come to pass. In this case, I believe we may find our answer here."

Harry watched as Dumbledore stood, peering into the basin. There was a liquid inside it, which seemed to be what was glowing.

"What is it?" Harry asked.

"I am not sure," Dumbledore replied. "But I believe the Horcrux may be within it."

"So…" Harry looked down at the body at the bottom of the basin. "Do you think he's here to guard it or something?"

"He would be a rather poor guardian, to let us get this close," Dumbledore replied. "No, Harry, I believe Regulus Black may be here for the same reason that we are."

"What- To steal the Horcrux? But Sirius said he was a Death Eater!"

"Did Sirius not tell you what he heard about his brother's death?"

Harry frowned, trying to remember the details of that conversation back in Grimmauld Place. "He said… He said Regulus was killed by Voldemort. He said he tried to back out of the Death Eaters, but he couldn't, and Voldemort killed him."

"That was the story as Sirius believed it," Dumbledore agreed. "But there was never any evidence of Regulus Black's death. He simply disappeared. I don't believe Lord Voldemort or his Death Eaters ever took credit for the death. Of course, he was far from the only person who vanished during the war, but his case was dissimilar to most of the others."

"Why, sir?"

"Because few people tried to back out of the Death Eaters, and those who did were always made an example of. Always, except for Regulus Black."

Harry looked down at the body again. "But sir, why would Regulus's body be here? And if he's alive, why hasn't he aged?"

"Both very good questions, Harry," Dumbledore replied. "Allow me to engage in a small amount of conjecture. It is possible that Regulus Black, whom I recall as having a very sharp intellect, may have realized Lord Voldemort's secret, just as I did. Sirius believed that his brother tried to back out of the Death Eaters; I would posit that he took it a step further and wished to stop Lord Voldemort. If he did, and if he knew enough to come here, there is one question that remains to be answered."

"What is it?"

"Did Regulus succeed in getting his hands on the Horcrux?"

Harry looked down at the young man slumped on the ground, then back up at Dumbledore. "How do we find out, Professor?"

Dumbledore pointed his wand at Regulus's still figure. "We ask him."

Harry watched, gripping his own wand tightly, as Dumbledore bent over Regulus and whispered, "Rennervate!" At first, Harry didn't think the spell would work - surely more powerful magic would be necessary to break this sort of enchantment - then Regulus's eyes slowly fluttered open.

His irises were almost the same exact shade of gray as Sirius's, a fact that made Harry's stomach twist. His eyes were bleary and unfocused, and he squinted in the dim light. "Professor?" he whispered after a moment. He looked to Harry and frowned. "Potter? What-"

Harry could see the exact moment Regulus recognized his surroundings. His eyes widened, and he tried to jerk upright before gasping in apparent pain and curling around his torso. Automatically, Harry knelt by his side and tried to put a hand on his shoulder, but Regulus flinched away before he could touch him.

"What's happening?" he demanded hoarsely. "Is this… Are these more hallucinations? Why would I see you?"

"I can assure you, Regulus, we are not hallucinations," Dumbledore said. "Will you tell me why you are here?"

Regulus pulled back, leaning against the basin. "Why are you here?"

Harry wanted to speak, but he wasn't sure if he should. He looked to Dumbledore, who was studying Regulus intently.

"If you will not tell me why you are here," he finally spoke, "I will tell you my thoughts, and perhaps you may deign to tell me if they are correct. I believe you are here because you wish to destroy Lord Voldemort's Horcrux that is hidden in this cave."

Regulus flinched so violently Harry thought he would fall over. "You- How do you know?"

"After all," Dumbledore continued, "there is little other reason to visit such a place. Judging by your state, I believe you triggered an enchantment that myself and young Mister Potter did not. Or perhaps…" Dumbledore looked above Regulus's head at the glowing basin. "Perhaps a potion."

Harry looked at the basin, then gaped at Regulus. "You drank that?"

"The potion has to be drunk to get at what's underneath," Regulus replied, visibly bristling.

"And that would be the Horcrux, correct?" Dumbledore asked.

Regulus looked away and nodded once, tightly.

"And did you get to it?"

Regulus nodded again.

"What was it?" Harry asked. "Which one?"

Regulus looked at him sharply. "You mean he really did make more than one?"

Harry nodded. "We think he made six."

"Six?" Regulus's eyes widened. "How has what's left of his soul not collapsed?"

"Can that happen?" Harry demanded.

"Regulus," Dumbledore cut in. "Which Horcrux was in the basin?"

Regulus looked up at Dumbledore, then ducked his head again. "A locket once owned by Salazar Slytherin."

"And where is it now?"

"Hopefully destroyed."

"Hopefully?" Harry repeated. "You don't have it?"

Regulus's jaw was tight. "I came here with my house elf. He was under orders to take the locket and destroy it."

"But he left you here," Harry protested. "Does that mean something went wrong?"

Regulus refused to meet his eyes, and Harry understood. "Oh."

"Your house elf would be named Kreacher, would he not?" Dumbledore asked.

Regulus's lips twisted, just slightly. "I suppose those who said Dumbledore knew everything was right."

"Not everything, certainly, but I do know a great many things," Dumbledore agreed amicably. "And the things I do not know, I can often guess. For example, I would guess that whatever this potion is, it put you in a state of suspended animation. You were preserved perfectly, most likely so that anyone who got this far would be trapped and kept for Lord Voldemort to interrogate when he discovered them here. You are lucky he has not visited while you've been here."

Regulus frowned slightly. "How long has it been?"

Harry looked over at Dumbledore, wondering if he would answer. For a moment, it seemed as though he wouldn't, then Dumbledore sighed.

"Today's date is the thirtieth of June, 1997."

Most of Regulus's expressions so far had been minute and clearly carefully controlled, but upon hearing the date, his jaw dropped. "No- No, you're joking. It can't- It's been eighteen years?"

Dumbledore inclined his head. "Many things have changed since you came into this cave, Regulus."

"But you're still looking for Horcruxes," Regulus said. "You're still trying to take down the Dark Lord. He's still alive."

"Unfortunately, yes."

Regulus took a sharp breath, then looked over at Harry. "I suppose you're not James Potter, then, if it's been eighteen years."

"Oh, er, I'm Harry, his son."

"Your father must still be in the Order, then, if you're going after the Horcrux." Regulus eyed him. "Are you even of age?"

"I'm sixteen."

Regulus looked at Dumbledore coldly. "So the Dark Lord isn't the only one who conscripts sixteen year olds, then."

"Mister Potter is a special case," Dumbledore said evenly. "As I said, many things have changed in the past eighteen years. We can discuss them, but I believe it would be a discussion better had outside this cave. If the Horcrux has been removed, there is no further reason to remain here."

Regulus hesitated a moment, then nodded tightly. Harry offered him a hand, which Regulus looked at blankly for a moment before accepting. Harry pulled Regulus upright, and almost immediately, Regulus began to list to the side before he was able to grab the basin for support.

"Now," Dumbledore declared, "we will need to make two trips across the lake, as the boat will only carry one of-age wizard at a time. Harry, may I have a word?"

Harry shot Regulus a quick look, wondering how much the sickly green tinge to his complexion came from the basin's light, then he stepped to the side with Dumbledore. "What is it, Professor?"

"I have a request to make of you," Dumbledore said quietly. "I cannot cross the lake with Regulus, but I do not believe he is in any condition to cross it himself, nor am I sure that the boat will move from shore to shore without someone directing it. The best solution to these problems that I have been able to come up with is for you to cross with me, then take the boat back to the island and cross again with Regulus. Do you feel comfortable with this arrangement? If you do not, we can of course discuss other options."

To be entirely honest, Harry didn't really love the idea of sailing through the body-infested waters on his own, nor was he entirely comfortable with sharing the small boat with a presumed-dead apparently-ex-Death Eater. Unfortunately, he couldn't see any other real options.

"I can do it, Professor."

"Are you certain, Harry?"

Harry nodded. "I can do it."

Dumbledore put a hand on his shoulder. "You are a very brave man, Harry. Your parents would be proud of you. Come, let us share our arrangement with Regulus."

Harry followed Dumbledore back over to Regulus, who was still leaning against the basin. "Now," Dumbledore stated, "as I said, the boat will only carry one of-age wizard at a time. As such, Harry and I will cross first, then Harry will return for you, Regulus."

A flicker of worry passed across Regulus's face, almost too quickly to be seen. Guessing the reason, Harry put in, "I'll come back for you, I promise. We're not going to leave you here."

Harry got the feeling that Regulus wasn't particularly thrilled that Harry had been able to read his expression so easily, but he just nodded once. Most of his weight was being supported by the basin by this point, and Harry wondered how much longer he'd be able to remain upright. He had the feeling Regulus had too much pride to sit now that he'd stood up, though. Sirius was always proud like that too.

"After you, Harry," Dumbledore said, gesturing at the boat. Harry jumped, then clambered into the boat. He could feel Regulus's eyes on them as Dumbledore followed him in and then sent the boat sailing across the lake. The darkness meant that the island went out of sight quickly, but Harry still thought he could feel that burning gaze.

"Sir," he said quietly, "what are you going to do about Regulus?"

Dumbledore sighed heavily. "I am still deciding about that, Harry. We will, of course, need to discuss the status of the Horcrux with Kreacher. As for everything else… Well, I believe we will simply have to deal with most of the upcoming issues when they arise."

Harry looked down at the water. "What he said, about Voldemort conscripting sixteen-year-olds…"

"As far as I know, Regulus Black was sixteen when he took the Dark Mark," Dumbledore said. "After Sirius ran away from home, Regulus became the new heir and took up the duties that Sirius had forsaken."

Harry thought about what Sirius had told him about his parents, then what he'd said about Regulus. He'd called his brother soft, but the young man on the island didn't seem soft, he seemed brittle. If you struck him hard enough, or at just the right angle, Harry thought he would shatter.

They reached the other shore, and Dumbledore stepped out of the boat. "Be careful, Harry," he warned. "I do not believe Regulus to be much of a threat, but you still ought to be on your guard."

"I will be," Harry promised, then the small boat set sail towards the island again.

The trip felt longer while Harry was alone in the boat, but eventually, he reached the green glow and clambered out of the boat. Regulus had lost his battle against gravity and was slumped at the foot of the basin again, curled slightly around his torso. Harry remembered how he'd gasped in pain before and wondered if it was another side effect of the potion that had left him comatose for eighteen years.

"Regulus?" he asked, holding out a hand. "I'm back. I've got the boat. We can get out."

Regulus looked up at him, slate-gray eyes narrowed. "Are you truly real?"

"I am," Harry promised. "You- You mentioned hallucinations before, but why would you hallucinate me? You weren't close to my dad, were you?"

Regulus's lip curled, just slightly. "No, James Potter and I were not especially close."

"Did you not like him?"

Regulus gave Harry a look, then took his hand and heaved himself to his feet. He tried to let go once he was upright, but Harry had the feeling he'd fall if left to his own devices, so he slung Regulus's arm over his shoulders and helped him over to the boat.

"It's not too long a ride," Harry promised as they sat down. "Or, well, you probably knew that already, didn't you? From when you came here?"

Regulus remained silent. He didn't say a word until Harry had already pushed off the boat and sailed away from the island, and then, it was only a single sentence.

"Does the Dark Lord truly still live?"

"Well, he was dead for a while," Harry replied. "But now he's back."

Regulus stared at him. "Explain."

"It's a long story," Harry hazarded, but Regulus's eyes didn't leave his face, so he awkwardly began. He didn't go into any details, but only told Regulus the story that the entire Wizarding World knew: that Voldemort had gone to kill the Potters, that his curse had rebounded when he tried to kill Harry, that he'd been in a deathlike state for over a decade after that, unable to do more than possess others, until he'd regained his body two years before. Regulus listened intently, and Harry could tell he was thinking hard about the information, even though he didn't say a word. When he finished the story, he waited for Regulus to say something, but he didn't, so they spent the rest of the boat ride in silence, until they bumped against the shore where Dumbledore waited.

"I trust the trip was uneventful?" Dumbledore asked Harry in an undertone as he offered him a hand out of the boat.

"He didn't do anything, sir," Harry reported. He turned back to the boat and offered Regulus a hand, which he took without hesitation, apparently now resigned to Harry helping him up. Harry thought he sensed Dumbledore's eyes on him, but when he turned back, Dumbledore was busy lighting his wand and seeking the exit.

"Do you have your wand with you?" Harry asked Regulus as he cast his own quiet lumos.

"Aren't you worried I'll attack you with it?" Regulus asked, reaching into his robes. "I am a Death Eater, after all."

"You're on our side now," Harry replied. "That's why you're here."

Regulus pulled out his wand and ignited its tip. In the shadows thrown up by sudden light, his face looked almost skeletal. "Indeed," he agreed, then said no more. Harry wondered if Regulus was always this taciturn and guarded, or if his behavior was a result of his situation. That would be more than fair, he thought, all things considered.

"Harry, Regulus," Dumbledore called, "we ought not to tarry."

Regulus was able to stand on his own, but he still swayed a bit as he walked, so Harry kept an eye on him as they followed Dumbledore out of the cave. Dumbledore slashed open his arm again to open the door, then led both Harry and Regulus out to the wet, windswept front of the cave. He didn't move to enter the water, however, and instead turned to look at Harry and Regulus.

"A plan must be made," he declared, "regarding what we will do with you, Regulus Black."

Regulus's grip tightened on his wand. "I thought we ought not to tarry."

"Professor-" Harry began, but at the look on Dumbledore's face, he closed his mouth. He had agreed to do whatever Dumbledore said, after all, and even though he thought Regulus seemed trustworthy - or at least trusted that they had the same goals - the end decision wasn't his to make.

"As far as the Wizarding World is concerned," Dumbledore began, "Regulus Black is dead and has been for eighteen years. I would assume, Regulus, that you do not want to disabuse the world of this notion quite yet, especially in regards to your old comrades in arms."

Regulus's mouth twisted, just a little. "I doubt it would do any of us any good."

"Very well, then. Instead, I propose that you and Harry return to the headquarters of the Order of the Phoenix."

"Professor," Harry protested immediately, "what about going back to Hogwarts?"

"I will return to Hogwarts," Dumbledore replied. "Trust me, Harry; if anything is amiss there, I will deal with it. As for yourself and Regulus, I will send someone to see to you at the headquarters, and then you may also return to the school, once everything is settled."

"And if I don't agree to these terms?" Regulus asked.

"Forgive me, Regulus, but I believed you smarter than that. And even if you were to disagree, you are in no fit state to fight your way out, especially not against myself."

Harry could see Regulus's knuckles go white with how tight his fists had become, but after a moment, his hands relaxed somewhat, and he nodded once. "Very well. I'll return with you to your headquarters. I assume we'll figure out future plans once you settle things at Hogwarts."

"I will be sure that everything is settled," Dumbledore agreed. "Now, we'll have to swim a ways before we're able to Apparate. The water looks to be just as bracing as it was before. Come, let us get moving."

Harry looked over at Regulus, wondering if he should say something, then he stowed his wand in his pocket and followed Dumbledore into the water. A moment later, he heard a light splash as Regulus followed suit.

"I trust you," Harry told Regulus quietly, as they swam behind Dumbledore. He tried to pitch his voice so it was just loud enough for Regulus to hear, but not loud enough for Dumbledore to catch. "And the Order will be fair."

Regulus hummed noncommittally. Harry wanted to say something else, but before he could, they reached a boulder that jutted out of the sea and clambered onto it, and Dumbledore held out both hands.

"I'll bring you two along with me, I believe, then carry on to Hogwarts."

Harry took Dumbledore's right forearm, just above where the curse blackened his hand, and Regulus took his left. Dumbledore spun on the spot, and after the now-familiar but still unpleasant feeling of being squeezed very tightly and then spat out, Harry found himself just outside of Grimmauld Place.

"Why are we here?" Regulus demanded, looking around. "This is my family home. What are we doing here?"

"The headquarters of the Order of the Phoenix," Dumbledore told him quietly, "can be found at number twelve, Grimmauld Place."

"That's my family home," Regulus repeated, and Harry thought he heard a note of panic in his voice. "How can this be the headquarters of your Order?"

Dumbledore leaned forward and pushed open the door. "Harry, I would ask you to explain what you know, and I will send an Order member who will be able to explain more details. For now, however, I must leave you two."

For a moment, Harry thought Regulus might grab Dumbledore's robes or do something to keep him from Apparating away, but he didn't; Regulus just watched as Dumbledore spun into nothingness, then turned to Harry and demanded, "Explain."

"We should go inside first," Harry replied. "Er, keep quiet when we enter, okay? There's a portrait that likes to scream a lot."

Regulus didn't look especially pleased to be given orders on the doorstep of his own family home, but he kept his mouth shut as they entered Grimmauld Place and carefully closed the door behind them. Harry led Regulus down to the kitchen, then tentatively sat down at the table and gestured for Regulus to sit across from him.

"What do you want to know?"

"This house belongs to the Black family," Regulus stated. "It has been passed down through the male line for generations. There is only one Black who would allow it to be used as the headquarters for an organization like your Order, so I have to assume that at some point in the last eighteen years, my parents died and Sirius inherited the house."

"They did."

Regulus looked around. "Sirius swore never to come back here, but I suppose the protections the Black family has been laying on the house for generations were beneficial to a vigilante organization. I doubt even the Dark Lord could break them."

"That's what Sirius told me," Harry agreed.

"And where is my brother now?" Regulus asked. "Off on some fool mission for Dumbledore? That's most of what he did after graduation. I suppose it's too much to ask that he's found himself some sort of reputable profession."

Harry should have known, of course, that Regulus would be ignorant of what had happened to his brother. He'd been trapped in that cave for eighteen years, after all; he couldn't possibly know what had happened to Sirius last year. Still, though, the thought of explaining it… It had been just over a year since Sirius's death, but that didn't mean the hurt was gone.

But Regulus was Sirius's brother, and he deserved to know what had happened to him.

The hesitation must have told Regulus that the answer wasn't one he would like. The slightest flicker of fear crossed his face. "Potter, where's my brother? Where is Sirius?"

"Sirius…" Harry swallowed hard. "Sirius is dead. He died last year."

Regulus's face went entirely white. "How did it happen?"

"There was a fight," Harry explained, a bit feebly. "At the Ministry. He was killed by Bellatrix Lestrange."

"Cousin Bella?" Regulus repeated. "She… She killed Sirius?"

"I'm sorry."

Regulus scoffed. "Honestly, it's a miracle he survived that long," he dismissed, but Harry could hear the slight tremble in his voice. "Sirius was always a foolish idiot, and Bella's always hated him, especially in the past few-" He hesitated. "Especially since Bella joined the Death Eaters and Sirius joined your Order. Of course she would seize the opportunity if she got it."

"Regulus-"

"If Sirius is dead, who owns the house?" Regulus asked. "If I was declared dead, I wouldn't be in the line of inheritance, so that means the next in line would be… Bella herself. Unless, of course, Sirius left the house to someone else."

"Me," Harry admitted awkwardly. "Sirius was my godfather. He left everything to me."

"So it's your house now, then," Regulus said, something cold in his tone. "It's all yours."

"You can still stay here," Harry offered quickly.

Regulus's lips twisted into a cruel smile. "How kind of you, to let me stay in my own ancestral home."

Harry's temper flared, but he did his best not to give into it. "It's not my fault that Sirius left it to me. He thought you were dead."

"He'd have left it to you even if he didn't," Regulus replied bitterly. "He did love his replacement brother more than he ever loved me."

"Regulus-"

"If Sirius left you everything, did he leave you Kreacher?" Regulus interrupted. "Or has he died in the last eighteen years as well?"

"No, Kreacher's still alive," Harry replied quickly. "He should be at Hogwarts. I- I told him to work there."

Regulus didn't look like he liked that idea very much. "Well?"

Harry stared. "Well, what?"

"Kreacher won't answer my call anymore," Regulus explained. "And we might as well ask him if he managed to destroy the Horcrux."

"Oh, right." Harry nodded. "Um, Kreacher?"

With a loud crack, Kreacher appeared on the table, facing Harry. He gave him a deep bow, one that managed to look highly sarcastic. "Master," he croaked, then he added in a mutter, "what a shameful master he is, friend to Mudbloods and blood traitors, nasty little-"

"Kreacher," Regulus stated from behind him, making Kreacher freeze immediately, "is that any way to speak of your master?"

"Master Regulus?" Kreacher whispered, turning around. "Kreacher thought Master Regulus was dead! Kreacher followed his orders, Kreacher left Master Regulus, Kreacher told no one what they had done-"

"Good," Regulus replied. "No one knew?"

"No one knew," Kreacher confirmed.

"And the Horcrux?" Regulus asked. "Did you destroy it?"

Kreacher froze.

"Kreacher," Regulus said slowly, "did you destroy the locket?"

Kreacher, to Harry's horror, burst into noisy tears. "Kreacher could not destroy it!" he wailed. "Kreacher tried everything he could, but nothing made a mark! Kreacher tried to open the locket but it would not open, and Kreacher punished himself, but the locket would not break, Kreacher failed!"

Regulus's lips thinned slightly. "Where's the locket now?"

Kreacher hiccuped. "Gone."

"Gone?" Regulus repeated, the word laced with a sudden fury that made Kreacher flinch. He must have noticed that, because his voice was forcibly calmer when he asked, "What happened to it?"

"Master Sirius tried to get rid of the family heirlooms, but Kreacher saved them, yes he did," Kreacher muttered. "Kreacher stole back the locket, but then the thief came, Mundungus Fletcher stole it all and ran before Kreacher could stop him."

"Wait a second," Harry said, something suddenly clicking in his brain, "are you talking about that locket in the drawing room that no one could open? The one we threw out?"

Kreacher shot Harry a baleful look. "Kreacher would not allow the Black heirlooms to be thrown out like common trash."

"Of course not," Regulus agreed. "But you said it was stolen?"

Kreacher nodded. "Mundungus Fletcher took the locket, dirty thief that he is, he took the locket and the Order of Merlin and the goblets and-"

"I saw him," Harry said suddenly. "I saw him in Hogsmeade, selling stuff."

"Did either of you stop him?" Regulus asked tightly.

"He left before I could," Harry admitted.

"The thief ran!" Kreacher cried. "Kreacher could not stop him!"

"Why didn't you go after him?" Harry asked.

"He couldn't," Regulus answered. "Sirius had thrown everything out, so it was no longer Black property. If he hadn't, Kreacher could have gone after him for stealing from his master, but he couldn't go after a wizard for stealing from him. House elves don't have those sorts of rights."

"That's horrible!" Harry cried, wondering suddenly if Hermione might have had more of a point with SPEW than he'd thought.

"He can go after this Mundugus Fletcher if you give him the order, though," Regulus said. "He'll be able to do a better job of it than either of us."

"Right," Harry agreed with a nod. "Er, Kreacher? I want you to find Mundugus Fletcher and, er, bring him to me. Or, bring him here and then tell me."

"I doubt I'll be leaving this house very often," Regulus offered. "I can deal with Fletcher, once Kreacher brings him back."

Harry didn't doubt that Regulus could deal with Mundugus, but he didn't like the idea of setting an ex-Death Eater on a member of the Order, even if that member was a thief. "You should still tell me, Kreacher."

"Kreacher will tell Master," Kreacher agreed. "Kreacher will find Mundugus Fletcher and drag him here by his filthy hair."

"And Kreacher…" Harry turned to Regulus. "Can I give him permission to go after people for stealing from him?"

"Unfortunately, no," Regulus replied. "Not without claiming his property as yours."

"Can I give him permission for this stuff that Mundugus stole specifically?"

Regulus's lips twitched in the first hint of a true smile that Harry had seen on his face so far. "I don't see why not."

"Then, Kreacher, you have my permission to take your things back from Mundugus when you find him. If he tries to fight you on it, tell him he can take it up with me."

Kreacher's expression looked guarded but tentatively hopeful. "Kreacher is allowed to keep his things?"

"You can keep them," Harry agreed. "We were just going to throw them out, so if you want them, you can have them."

Kreacher looked dangerously close to bursting into tears again. He looked from Harry to Regulus, then he gave them both very deep bows. "Kreacher will find Mundugus Fletcher and bring him here. Kreacher will find the locket and his things. Kreacher will do as his master says."

"Good luck," Harry offered. Regulus just gave Kreacher a nod, then Kreacher vanished with a loud crack.

"Oh," Harry said, just after he disappeared, "I forgot, I was thinking we should see if you can give him orders."

"You're his primary master," Regulus replied. "If Kreacher is still bound under the same rules he used to be, he should answer to any member of the family, but considering I'm officially considered dead, I'm not sure he'll have to listen to me."

"Will he listen anyway?" Harry asked. "He seems to like you."

Regulus's mouth twisted. "Perhaps he does, but I don't deserve it."

It was, Harry thought, the most vulnerable thing he'd heard Regulus say. Part of him wanted to ask for details, but he doubted they'd be forthcoming, and he wasn't sure the conversation would go well if he did. As such, Harry was searching for another topic to bring up when someone else Apparated into the room.

"My god," Remus Lupin whispered, staring at Regulus with wide eyes, "it really is you."

"Lupin," Regulus said, his voice dry. Any hints of vulnerability that Harry might have caught glimpses of were immediately gone. "I suppose Dumbledore sent you?"

"Professor," Harry said, relieved. "Is Hogwarts alright? Is Professor Dumbledore back?"

Lupin tore his gaze away from Regulus and turned to Harry. "Hogwarts was safe when I left it," he reported. "I assume it still is. How did this happen? I was with Sirius when he heard that Regulus died. I remember when he went to the funeral. How-"

"I don't believe it's anything that concerns you," Regulus said coldly. "Suffice to say, I am far less dead than I was presumed to be."

"You look so much like Sirius did at your age," Lupin said, almost fondly, then his face grew drawn. "Did anyone tell you-"

"I told him what happened to Sirius," Harry cut in, knowing that Lupin still hated to talk about it, even though it had been a year. Harry couldn't blame him; he hated talking about it too.

"Did my brother follow you around like a dog until the end, then?" Regulus asked. Harry wondered why he sounded so cutting every time he spoke to Lupin. Perhaps there was a history there that Harry didn't know about. "Remaining ever faithful to the family he chose over the one he was born with?"

Oh, Harry thought ruefully, that might explain it.

"Does he not know about what happened to Sirius?" Lupin asked. "How he spent twelve of these past years?"

"I didn't bring it up yet," Harry admitted.

"What are you talking about?" Regulus demanded, his voice sharp. "How did Sirius spend twelve years?"

"When my parents died," Harry began slowly, "their house was under a Fidelius Charm. The Secret-Keeper was Peter Pettigrew, who turned out to be a Death Eater and a traitor, but everyone thought the Secret-Keeper was Sirius. So Pettigrew framed him, and everyone thought Sirius was the traitor, and…"

"And he went to Azkaban," Lupin finished. "He didn't even have a trial. He was assumed to be a Death Eater. Everyone knew what his family was like. He was in Azkaban for twelve years, until he managed to escape."

Regulus looked ill. There had been something cutting in Lupin's voice when he mentioned Sirius's family, and Regulus had caught it just as much as Harry had. It wasn't quite fair. It wasn't quite wrong either.

Lupin looked at Regulus for a moment, then sighed and ran a hand through his hair. "How much have you told Regulus, Harry?"

"I told him about Voldemort, and I told him about Sirius," Harry said. "Nothing that detailed, though."

Lupin nodded to himself. "I'll make tea," he declared, "then we should do our best to get Regulus up to speed. It's been a while, after all."

"Does Regulus get a say in this?" Regulus drawled.

"Does Regulus have an objection?" Lupin countered.

"Has my room been ransacked in the way the rest of the house has?"

Lupin twitched. "Sirius never went in your room."

Some flicker of expression passed over Regulus's face, but it was gone too quickly for Harry to tell what it was. "Then it should still be habitable. I'm going to retire there for the evening."

Lupin looked like he might be about to say something, but Harry cut in quickly. "Do you want anything to eat first?"

It was clear Regulus hadn't been expecting that question. He'd been preparing for a fight, and the gentle offer took the wind out of his sails. "No, thank you," he said stiffly. Harry remembered how ill he looked before, thought of the way even now Regulus seemed to move gingerly, and wondered if he was worried about keeping it down.

"If you want anything, you can ask," Harry said. "I don't know if your things are all still in your room, but if you need clothes or anything, you could borrow mine."

Regulus nodded, just a bit. "Thank you."

He turned to go, but before he could, Lupin called out, "Wait. Is that blood on your sleeve?"

Harry frowned, looking at Regulus's sleeves. One of them did appear to have blood on it. Regulus looked like he wanted to leave anyway, but apparently he didn't like his chances, because he didn't protest when Lupin went over and gently took his arm. There definitely was blood on the sleeve, a lot of it, and when Lupin pushed it up, Regulus's forearm was a bloody mess as well.

"What happened?" Lupin asked, his voice gentler than it had been since he first arrived at Grimmauld Place.

"A bit of bloodshed was necessary," Regulus said flatly. Harry realized Regulus must have cut himself to get into the cave. "I can deal with it myself."

"I've picked up a fair amount of healing spells recently," Lupin replied as he began to siphon the blood off Regulus's arm with his wand.

And, as he did so, he revealed a sickeningly familiar tattoo.

Regulus pulled his arm away, pushing the sleeve back down, but it was too late. The Dark Mark on his forearm had been perfectly visible, including the cut that sliced down the middle of it. Harry absently wondered if the cut would interfere with the abilities of the Mark. Lupin looked a bit more startled, perhaps by the fact that he'd been touching the Dark Mark without knowing. It wasn't like it was a surprise that Regulus had it, after all. Lupin knew he'd been a Death Eater.

"I said, I can deal with it myself," Regulus said icily. "I'm going to retire. Goodnight."

"If you need anything, just ask," Harry called as Regulus swept out of the kitchen. Regulus didn't reply, but Harry didn't hold it against him; he was clearly at the end of his rope, and Harry didn't blame him for it. He had no idea what he would do if he woke up eighteen years in the future, especially if he woke to find out that Voldemort was still around. Regulus had a lot to think about, and that wasn't even taking into consideration the fact that he seemed to have expected to die in the cave. Being alive at all must have been a surprise.

"Well," Lupin finally said, "I can tell you that when Albus told me Regulus Black, of all people, was alive and at Headquarters, I didn't entirely believe him. Where did you find him, Harry?"

"I don't know if I can tell you," Harry admitted. The Horcruxes were a secret few people knew, and Harry had to assume that, if Dumbledore wanted the Order to know about them, they'd already know. "But he had drank some sort of potion that put him into suspended animation, so Professor Dumbledore and I woke him up."

"Albus said something about Regulus attempting to destroy Lord Voldemort?" Lupin prompted.

"Yeah, that's how he ended up like he was," Harry agreed. "It's kind of a long story, and I don't know how much Professor Dumbledore would be okay with me sharing."

"I understand," Lupin said, nodding. "Are you hurt at all, Harry? Or do you need anything else?"

"I'm fine," Harry said quickly. Lupin was still looking at him, almost expectantly, so he added, "Er, maybe a little hungry?"

"I'll see what we can find in the kitchen, then," Lupin declared.

Harry watched Lupin begin searching through cupboards. "Do you know if I can go back to Hogwarts?"

"Albus wanted to settle a few things there, then he planned to return here, I assume to talk with you and Regulus. He told me he would bring you back to Hogwarts then."

"And everything there seemed normal?"

"Everything seemed normal," Lupin agreed. "Is there something specific you're worried about?"

Harry remembered Trelawney telling him about the strange whooping she'd heard in the Room of Requirement. The conversation felt so long ago now, even though it hadn't been very long at all. It wasn't proof, though, and no one had seemed particularly inclined to listen to Harry, so he just said, "Just a bad feeling. I'm worried someone might try something while Professor Dumbledore's away."

"Even when Albus is gone, the school is hardly left unguarded," Lupin replied. "I assure you, Harry, Hogwarts is perfectly safe." With a noise of triumph, Lupin pulled a loaf of bread out of one of the cabinets, as well as a jar of jam. "It's not much, but I don't think there's anything else. Most of us don't spend enough time here to keep much food in the kitchen."

"That's fine," Harry assured him. "I'm not that hungry."

Lupin passed the bread and jam over to Harry, and Harry made himself some half-hearted toast. He was distracted enough that he almost burned the bread while toasting it with his wand, but Lupin was kind enough not to mention that.

"Will you tell me more about Regulus Black?" Harry asked after a moment. "All I know is what Sirius told me, and it's not much."

Lupin sighed, sinking into one of the chairs around the kitchen table. "I never spent much time with Regulus. He was a Slytherin, after all, and his relationship with Sirius was often… contentious. I do think they loved each other, but neither of them knew much how to show it. Considering the house they grew up in, I suppose that's not surprising. Sirius was always the troublemaker in his family, and my impression is that Regulus was the good child. He did as his parents said, and he didn't make waves at Hogwarts except for the ones he was supposed to make. I believe their parents would sometimes hold Regulus up as an example for Sirius, which Sirius didn't particularly enjoy. I'm not sure Regulus would have enjoyed it either, but of course I never spoke to him about it."

"Sirius said he was soft," Harry said. "It seems like he thought he was stupid and bought into everything their parents said. But if he really bought into everything, he wouldn't have tried to defeat Voldemort, would he?"

"You'll have to speak to Regulus about that," Lupin said. "I truly didn't know him that well."

"You never spent any time with him?"

Lupin hesitated. "There was one time. Regulus was in his second year, I believe. Things between him and Sirius were tense, but not nearly as tense as they got after Sirius ran away. Regulus and I were both in the library, and he was having trouble with a Defense essay. I offered to help, and he let me. I remember thinking that was curious, if he was as much of a little copy of his parents as Sirius painted him out to be. Surely they'd told him not to associate with me. But perhaps he thought the help I could give with his essay was worth risking his parents' displeasure. I helped him with the essay. He never spoke about it again, but I heard he got an O." Lupin shook his head slightly. "I haven't thought about that in years. I'd nearly forgotten."

"Was Regulus bad at Defense?" Harry asked.

"I believe Regulus had the same problem that Sirius sometimes had with Defense classes," Lupin said. "All of their previous teaching on the subject had been from the perspective of the Dark Arts, not the perspective of defending oneself from them."

"I know their mum was awful, but what about their dad?"

"Sirius didn't complain about him quite as much as he complained about his mother, but I don't think he was any better than she was. It was just that Sirius and his mother had an especially contentious relationship. He took after her, I've been told. Both of them were fiery. Regulus and his father, on the other hand, were calmer, but Sirius said that when his father was really, truly angry, it was cold and terrifying. He never said if Regulus was the same."

"I get the feeling he might be," Harry said, thinking about the way Regulus had acted so far. "I think he could be scary if he wanted to be."

"He was a Death Eater," Lupin said. "I know you know that, but it still bears repeating. He may have turned away from Voldemort, but I wouldn't trust him yet."

"Dumbledore said he was sixteen when he joined," Harry said. He didn't mention that Malfoy was also sixteen, which he had been told by multiple people meant Voldemort would be unlikely to recruit him. If he did it once, who was to say he wouldn't do it again?

"I believe Regulus joined the Death Eaters not long after Sirius ran away from home," Lupin said. "I only went up against him once, as far as I know."

"You fought him?" Harry asked, distracted from his initial line of questioning.

"At least once," Lupin agreed. "There may have been other times, but his mask hid him then. The one time I know I dueled him, his mask fell off."

"What happened?" Harry asked. "Were you with Sirius?"

"I was not. As for what happened… Regulus was a very accomplished duelist, and if James had not come to provide me with backup, he may well have beaten me. As it was, we were able to push him back. One of James's spells knocked his mask off, and he Disapparated immediately after. I believe he hoped to leave quickly enough that we wouldn't recognize him, but that was unsuccessful."

"How old were you all?"

"It was the summer after I graduated," Lupin said. "James and I were eighteen. Regulus was seventeen."

Harry took a bite of his toast, thinking. Perhaps it was partially his affection for Sirius coloring his opinions on his little brother, but he couldn't help but see the tragedy in Regulus's story. It seemed like Regulus had been pushed into being something, and then he'd realized it wasn't what he wanted to be and nearly died in an attempt to become something else. It made Harry think about Malfoy in a slightly different light, to be honest. Wasn't it possible he could also have been pushed into becoming something? His father was a Death Eater and his mother was Bellatrix's sister and basically a Death Eater herself, if not quite in name. Could Malfoy be like Regulus?

Well, Harry supposed, that depended on whether Malfoy ever gained enough of a spine to turn against Voldemort. And, perhaps, if he ever realized that what Voldemort was doing was wrong. It was that aspect of Regulus's story that made Harry think he wasn't entirely irredeemable.

"Harry," Lupin said seriously, as if he'd sensed the direction Harry's thoughts were going, "you need to be careful around Regulus. Until we know more about his plans, we need to assume he could be dangerous."

"I'll be careful," Harry promised. "I don't know if I'll even be spending that much time with him. I'll go back to Hogwarts as soon as Dumbledore says I can."

"I'm surprised he hasn't sent us a message yet," Lupin said, a slight frown on his face. "It shouldn't be taking him this long."

"Do you think something's wrong?" Harry asked. "Could something have happened?"

"I'd think someone would have sent the word out," Lupin said, his frown deepening, "but I suppose something could have happened."

"Can you send a message?" Harry asked, his stomach tightening. Something must have gone wrong. He could feel it. He'd been worried it would, and he'd told Dumbledore that Malfoy's plans were coming to fruition, but no one had listened to him.

He hoped his friends were alright. He hoped asking them to keep watch hadn't gotten them killed.

Lupin pulled out his wand and flicked it. A silvery light shot out of the tip and sped out of the room. "I'm sure it's nothing serious, but I'm sending a message to Minerva, just in case."

Harry wondered what exactly Malfoy had been planning. Whatever it was, he thought it would be happening that night - and possibly had already begun - but he didn't know what it would be. Maybe he could have figured out more, if he'd put more effort into figuring it out, if he'd done more to track Malfoy down, if he'd tried harder to get into the Room of Requirement…

A moment later, a silvery cat appeared in the kitchen and leapt onto the table. The Patronus opened its mouth and spoke in Minerva McGonagall's voice, and it said three words that changed Harry's life, and the Wizarding World, forever.

"Albus is dead."

---

No one knew exactly what had happened. No one witnessed it. But over the course of the next hour, while Harry sat at the kitchen table in Grimmauld Place and tried not to drown in the sudden loss, the others were able to put together a vague timeline of events.

About an hour after Harry and Dumbledore left, which was about the same time that Dumbledore returned to Hogwarts, Malfoy left the Room of Requirement. He must have somehow gathered Death Eaters there, although no one was quite sure how, and then they all left under the cover of Peruvian Instant Darkness Powder. The Order caught up with them around the Astronomy Tower, where a fight broke out. Some of the Death Eaters, including Malfoy, went up into the tower, but no one else could follow them up. Snape arrived, somehow made it up the stairs into the tower, and then came back down a few minutes later, Malfoy in tow. They ran, and the Order let them go, assuming they were running from the Death Eaters. Snape yelled something, although no one heard him well enough to know what it was, and all the Death Eaters left. Snape and Malfoy left as well.

And at the bottom of the Astronomy Tower, they found the broken body of Albus Dumbledore.

They didn't know who did it, but Harry had his suspicions. Malfoy must have had a reason for bringing all the Death Eaters into Hogwarts that night. There had been something he was supposed to do. Maybe it was just allow for an invasion of Hogwarts, but Harry had the feeling that hadn't been his only goal. And if Snape had made an Unbreakable Vow to help him…

Harry guessed that Malfoy's task had been to kill Dumbledore. Dumbledore had ended up dead. The only question was, had Malfoy done it, or had Snape?

"We should leave Grimmauld Place," Lupin told Harry, his face drawn, once they determined that Snape had definitely left with the Death Eaters. "If Snape has truly joined the Death Eaters, he could lead them here. With Dumbledore dead, everyone who knew the location of our headquarters is a new Secret Keeper, including Snape."

"Where will we go?" Harry asked. "Is Hogwarts any safer?"

After all, Dumbledore had died there, and from what Harry heard, Bill had been attacked by Fenrir Grayback. Everyone else had come out with only superficial injuries, at least on their side, but if Harry was meant to avoid anywhere a Death Eater could go, Hogwarts was no safer than Grimmauld Place.

He'd nearly died at Hogwarts many times, but it had still always been his safe place. It wasn't anymore.

Lupin looked pained. "I think going back to Hogwarts is for the best."

Harry considered arguing more, but he didn't the energy to do it. "Alright," he agreed. He stood, then suddenly remembered who was sleeping upstairs. The events of that night seemed distant, ancient, but if they were going to flee, they should bring Regulus with them.

"I need to get Regulus," Harry said. "He should come too."

"I'll send a message to Minerva to expect him," Lupin agreed, apparently also unable to summon the energy to fight Harry on it, despite what he'd said before about not trusting Regulus.

Harry went upstairs in something of a haze, wondering if he'd recognize Regulus's room when he saw the door. He'd never gone to Sirius's room either, but he knew it was on the topmost floor, so he went up there, figuring Regulus's bedroom was probably nearby. He was right; there was a sign on one of the doors that read "Do Not Enter Without the Express Permission of Regulus Arcturus Black."

Harry knocked on the door, wondering if Regulus would hear it or if he was asleep. Apparently, he was still awake, because a moment later, the door opened, revealing Regulus on the other side.

"Potter. What is it?"

"We need to go to Hogwarts," Harry said. "We're not safe here."

Regulus frowned. "Why? What happened?"

Harry's lips felt suddenly numb. Could he say it aloud? Wouldn't say it make it real?

It was real either way. He knew that. Saying it aloud wouldn't change anything. It had already happened, and keeping quiet couldn't change that. He had to say it.

"Dumbledore is dead."

Regulus stared at him. Some little part of Harry's mind noted that he seemed to do that when he was surprised. "What happened?"

"We don't know the details," Harry said, "but a group of Death Eaters got into Hogwarts, and one of them must have killed Dumbledore."

"And we're going to Hogwarts?" Regulus demanded. "Wouldn't it be safer to stay here?"

"No, because the person who might have killed Dumbledore was someone we thought was a member of the Order, and he knows where Grimmauld Place is. With Dumbledore dead, he can bring anyone he likes here. The Fidelius Charm won't work properly anymore."

The person they trusted, the person Dumbledore trusted, the person Harry had never liked but never thought was this evil-

"We can come up with more defenses," Regulus said, somewhat dismissively. It was enough to break Harry out of his spiraling thoughts and back into reality. "You own this house. If you activate all of the protections my family has set up, no one will be able to get in here if you don't want them to."

"I don't know how to set up those protections, though," Harry countered. "And my friends are back at Hogwarts. We need to go."

Regulus pressed his lips together. He didn't look particularly happy, but he didn't argue anymore, just nodded and stepped out of the room. He was wearing a different set of robes than he had been before, Harry realized, but he was still dressed. No matter how tired he was, he clearly couldn't sleep.

Harry understood that feeling all too well.

They went downstairs to the kitchen, where Lupin was waiting. "Minerva has set up a Floo connection between this fireplace and the one in her office," he told them. "I told her about you, Regulus. She'll keep her office empty, so you can stay in there until we figure out what to do with you."

Regulus didn't look particularly fazed. "As I've already told Potter, we can set up protections here that will keep the house safe, even if you have a traitor in your midst who is no longer gagged by the Fidelius Charm. I will admit it makes sense to regroup at Hogwarts, but then I intend to return here."

"Making Grimmauld Place safe again is not our first priority, but we'll do it soon, I'm sure," Lupin agreed. He seemed remarkably calm, but Harry had seen the way he'd reacted when McGonagall's Patronus first told them the news. He'd looked like he'd gotten a Stunning Spell straight to the chest, and he'd sank into a chair immediately and buried his face in his hands. If he seemed calm now, Harry was certain he was faking it. "For now, we should go to Hogwarts."

With a flick of his wand, Lupin lit the fire in the fireplace, then he took a handful of Floo powder out of the jar on the mantle and tossed it in. "Minerva's office, Hogwarts," he declared, and the flames turned emerald. Lupin gestured for Harry and Regulus to go through.

Regulus looked over at Harry. "After you, Potter."

Harry nodded and stepped into the flames. After the usual disorienting feeling of traveling via Floo powder, he tumbled out onto a soft carpet. A hand entered his field of vision, and Harry let McGonagall help him up.

"Potter," McGonagall said, her voice trembling slightly. "I'm glad to see you're alright."

"Was anyone else killed?" Harry asked.

"No," McGonagall said, shaking her head. "Bill Weasley was injured, but his injury was the only serious one. There was one Death Eater casualty, a man named Gibbon."

Dumbledore must have been the target, then. Harry couldn't imagine that the Death Eaters would have left like that otherwise, not with only one casualty. But with Dumbledore dead… Well, that must have been enough of a blow that Voldemort would be satisfied with it.

Harry hoped it wouldn't be enough to break them, but he wasn't sure that was the case.

Before he could say anything else, Regulus stepped smartly out of the fireplace, somehow managing not to fall. He was pale, and Harry thought he could see the effort his smooth movements were costing him in his eyes, but he clearly refused to show any more signs of weakness than he absolutely had to.

"Regulus Black," McGonagall breathed. "Remus said you were back, but…" She looked to Harry. "Where did you and Albus find him?"

"Yes," Lupin agreed, also emerging from the fireplace, "where did you find him?"

"I can't tell you that," Harry said, shaking his head. "The thing Dumbledore and I were doing tonight… It was secret. No one else is supposed to know, not even the Order."

Harry could see Regulus looking him out of the corner of his eye, but he ignored it. They would talk later. For now…

"Professor, where's everyone else?"

McGonagall, who had clearly been about to argue, visibly relented. "I believe most of your friends are currently in the Hospital Wing with Bill Weasley. All present Order members are gathered there as well. Would you like to go there, or would you rather have me bring your classmates to you?"

"I'll go there," Harry said. "But after, could I bring Ron and Hermione back here, Professor?"

McGonagall nodded. "I'll keep this office empty. I'll have to coordinate plans, but I can do that from the Headmaster's-" She paused and swallowed, and Harry realized she was close to tears. "The Headmistress's office," she corrected herself. "But we will need to speak later, Potter."

Harry nodded. "I know." He'd expected as much. He wouldn't tell anyone anything, but he knew they'd still ask. He didn't blame them. No one else understood what he had to do, and of course, he couldn't tell anyone enough to make them understand. He'd have to just put off answering them for as long as he could.

"Will you be alright here, on your own?" Harry asked Regulus, turning to him.

Regulus nodded. "I can manage."

McGonagall waved her wand, and a plate of sandwiches appeared on the desk, along with a pitcher of pumpkin juice. "If you get hungry," she explained. "The door will be locked. You understand, of course."

"That you don't want another Death Eater running loose in the school?" Regulus asked, his mouth twisted into an expression that could also be called a smile, if not for the utter lack of humor on his face. "I understand perfectly, Professor."

Lupin ushered Harry out of the office, McGonagall behind them. "Potter," she said, once she'd closed and locked the door, "are you certain that Regulus Black's mysterious return from the dead is unrelated to the events that occurred tonight? Could it have been meant as a distraction, or-"

"No," Harry said, shaking his head. "This wasn't part of Voldemort's plan. I'm sure of that."

"Can you be sure?" Lupin asked. "He was- is a Death Eater, Harry. That's not a position you can leave."

"I'm sure," Harry said, thinking back to Regulus's slumped form on the island. "Voldemort doesn't know about him. It wasn't his plan."

Lupin and McGonagall shared a look, then looked back at Harry. "If you say so," McGonagall said. "Come along. We should rejoin the others."

They walked to the Hospital Wing, Harry still in a bit of a daze. It was lightening, and he was growing more aware of his surroundings and the situation, but he almost wished it wouldn't. If the daze lifted, he'd have to live, fully aware, in a world where Dumbledore was dead. He wasn't sure he was ready for that yet.

The second they entered the Hospital Wing, a blur of red flew at Harry. "You're alright," Ginny whispered into his ear, clinging to him. "We- We were afraid-"

"I'm fine," Harry assured her. "I'm fine. Are you all alright?"

"Neville got hurt, but Madam Pomfrey says he'll be alright. Professor Flitwick got hurt too, but he'll be alright too. And then Bill…"

Over Ginny's shoulder, Harry could see Bill, lying in one of the beds. At least, he assumed it was Bill; the person's face was bloodied and mauled. Fleur and Mrs. Weasley were sitting at his bedside, both crying and holding hands. Harry didn't have the energy to wonder too much about how that had come to happen.

Ginny finally released Harry, and Hermione, who had come up next to them, quickly took her place and gave Harry a tight hug. Ron and Luna had come up as well, while Tonks and Mr. Weasley had gone over to speak with Lupin and McGonagall.

"You're all alright?" Harry asked when Hermione finally released him. He scanned his friends, but luckily, saw no signs of injury on them.

"We're alright," Ron agreed. "Your Felix potion sure is something, mate. Everything just seemed to miss us."

"What happened to Neville?" Harry asked, looking over at his bed, where Neville lay sleeping.

"He got grazed by a spell," Luna said, sounding more present than usual. "He was pushing me out of the way. It was very brave of him."

"Then he tried to go up the stairs after the Death Eaters, but there was some sort of barrier, and it threw him into the air," Ginny added. "But Madam Pomfrey says it's not too serious."

"What happened to you?" Hermione demanded. "We were expecting you to come back, and then Dumbledore did, and then-" She gulped, tears springing to her eyes. "No one said anything about you being with him, but we were all worried that you might have been."

"I wasn't," Harry said. "It's… a long story."

"Is it something you three want to talk about without me or Ginny being there?" Luna asked.

"Later," Harry said. "Right now, tell me more of what happened. Lupin and I heard everything secondhand."

The others all shared a look, then Ron told Harry how he and Neville and Ginny had been waiting outside the Room of Requirement, since they couldn't see Malfoy on the map, when he came out and immediately used Peruvian Instant Darkness Powder to blind them. He'd had his own Hand of Glory for light, and he'd led the Death Eaters out. Once Ron, Neville, and Ginny had managed to a place that had light, they ran into the Order and told them what was happening, and the fighting began soon after.

Hermione took over the narrative then, telling Harry about how she and Luna had been outside Snape's office. Flitwick had gone to Snape's office to tell him about the Death Eaters, and then Snape had come out and told Hermione and Luna that Flitwick had collapsed and needed help. "Oh, it's so obvious now," Hermione whispered, her face buried in her hands, "Snape must have Stupefied Flitwick, but we didn't realize, Harry, we didn't realize, we just let Snape go!"

"If you hadn't, he would have killed you," Harry said. "I think he was the one who killed Dumbledore."

"I think he probably was," Ginny agreed slowly. "Malfoy and a few other Death Eaters were in the Astronomy Tower, and they only came back out after Snape went up. And when he came back down, I think what he said was 'it's over.' I- I think he might have been in on the plan the whole time. Him killing Dumbledore might have been the plan."

"I think the plan was for Malfoy to kill Dumbledore," Harry said, aware his voice still sounded a bit dull. "But if he couldn't do it, Snape was supposed to do it instead. I bet it was Snape who did it in the end."

"How did they do it, though?" Ron asked. "I mean, Dumbledore held off You-Know-Who last year. He should have been able to hold off Malfoy and Snape and a couple of flunkies."

"Maybe he was holding them off," Harry said. "But he trusted Snape. He wouldn't have thought he'd have to fight him. If he was already fighting, if he was distracted…"

"He wouldn't have seen it coming," Hermione whispered in horror.

"What do you think the Death Eaters are going to do next?" Luna asked. When everyone looked at her, she added, "They must have a bigger plan. You-Know-Who must have done this for a reason. Do you think he's going to make another move?"

Harry looked at Ron and Hermione. Luna was right; this was probably the precursor to something bigger. With Dumbledore gone, there was no one strong enough to oppose Voldemort. He could do whatever he wanted.

Which was why Harry had to stop him.

"Ron, Hermione, I need to talk to you two in private," he said. "Ginny, Luna-"

"We understand," Ginny said, nodding.

"Should we help distract the others so they don't notice you leaving?" Luna asked.

"No, it's fine," Harry said. "Do you two- If you don't want to do this now-"

"We should do it now," Ron said. "We need to move fast, right?"

"Where should we go?" Hermione asked, her eyes still a bit teary but her face resolute. "The Common Room will be full of other students, I'm sure-"

"We need to go to McGonagall's office," Harry said. "There's something there I need to show you."

Ron's eyes went wide. "Did you find… one of them?"

"Sort of," Harry replied. "Come on."

"Sort of?" Ron echoed, following Harry out of the Hospital Wing. "What does 'sort of' mean?"

"I'll tell you when we get there."

Ron and Hermione followed as Harry led the way back to McGonagall's office. He was sure they were both bursting with questions, but they did an admirable job of holding them back until they entered the office. The second they did, Ron burst out, "Okay, so how could you have 'sort of' found- Merlin's pants!"

"Regulus, it's me!" Harry said quickly, pushing Ron out from in front of Regulus's wand. "These are my friends, Ron and Hermione. They know everything I know about the Horcruxes. I trust them. They're here to help."

Slowly, Regulus lowered his wand. "My apologies, then."

"Who the bloody hell are you?" Ron demanded.

"You look like-" Hermione broke off and looked over at Harry. "Did you call him Regulus?"

"Do you want to introduce yourself, or should I introduce you?" Harry asked Regulus.

"Go ahead," Regulus said, stowing his wand back in his robes. Harry noticed that his hand seemed to be trembling slightly, but he didn't say anything.

"This," Harry said, turning to Ron and Hermione, "is Regulus Black."

"Regulus Black?" Hermione echoed. "Sirius's dead brother?"

"Sirius's brother?" Ron repeated. "You mean the Death Eater one?"

"Only partially correct," Regulus drawled. "I am Sirius's brother. I am not dead. And I am no longer a Death Eater."

"Harry, what happened?" Hermione asked, wide-eyed.

"I thought you were looking for Horcruxes," Ron added. "Also, wasn't Sirius's brother only a few years younger than he was?"

"I was looking for Horcruxes," Harry said. "I mean, we were. Me and-" His voice wavered. "Me and Dumbledore. He knew where one was, so we went to find it. It was in this cave by the ocean. We went into the cave, and there was a lake with an island in the middle of it, so we went to the island, and we found Regulus."

"As a… guard?" Hermione asked slowly.

Regulus's lip curled. "No."

"Regulus stole the Horcrux, eighteen years ago," Harry said. "But to get it, you had to drink a potion, and the potion put him into suspended animation until Dumbledore woke him up."

"Then how did you steal the Horcrux?" Ron asked Regulus. "If the potion froze you?"

"I had help."

"Another Death Eater?"

"No."

Seeing that Regulus seemed to have no intention of elaborating, Harry jumped in. "It was Kreacher," he told Ron. "Kreacher went with Regulus to the lake, and he took away the Horcrux."

"And he left you there?" Ron asked. "Rotten little-"

"I told him to," Regulus said, his voice icy cold. "Kreacher was merely following his orders."

"You told him to leave you?" Hermione asked tentatively. "Did you know what the potion would do?"

"I thought it would kill me."

Hermione's eyes went wide. Ron's did as well. Harry's eyes went to Regulus, and he had the immediate feeling that Regulus hadn't meant to say that aloud.

That didn't mean, of course, that it wasn't true.

"So Regulus and Kreacher stole the Horcrux," Harry cut in before anyone else could say anything, "and then Kreacher brought it back to Grimmauld Place to try to destroy it. The problem was, he couldn't do it. And then, when we were cleaning out the house, we threw it out."

"What?" Ron and Hermione demanded in unison.

"Remember the locket no one could open?"

"That was the locket?" Ron asked. "That thing had a bit of You-Know-Who inside it?"

"Thank goodness we couldn't open it," Hermione breathed. "I'm not sure what it would have done, but I'm sure it would have been awful."

"Kreacher stole it out of the trash, but then Mundungus Fletcher stole it from him," Harry added. "Remember when we saw him selling Sirius's stuff in Hogsmeade? So I've told Kreacher to find Mundungus and bring him to me, so we can get the locket back."

"And then what?" Ron asked. "If Kreacher couldn't destroy it, how are we supposed to do it?"

"Horcruxes can only be destroyed by things that have no cure," Regulus said quietly. "Fiendfyre, for example, or basilisk venom."

"I stabbed Riddle's diary with a basilisk fang," Harry agreed.

"But with the locket, I suspect it must be opened before it can be destroyed," Regulus added. "And I have as little knowledge of how to do that as Kreacher."

"We'll figure it out when we get it," Harry said. "One thing at a time."

"And then what?" Ron asked. "We've still got more Horcruxes to go, right?"

"We think Voldemort made six," Harry said. "I destroyed the diary and Dumbledore destroyed the ring, and once we find the locket, we can destroy that too. Then it's just Hufflepuff's cup, Nagini, and something else that probably belonged to either Gryffindor or Ravenclaw."

"Hufflepuff's cup?" Regulus repeated, a slight frown creasing his brow.

"It's a long story, but the person who used to own Slytherin's locket, before Voldemort stole it, also had a cup that used to belong to Hufflepuff. It went missing at the same time as the locket, so Dumbledore" - Harry's voice barely broke on the name - "figured it was probably turned into a Horcrux too."

"Do you know where any of the other Horcruxes are?"

"Well, Nagini will be with Voldemort," Harry said. Noting the look of confusion on Regulus's face, he added, "Nagini is his pet snake."

"Did Voldemort not have Nagini during the first war?" Hermione asked curiously.

"Not as far as I can recall," Regulus replied. "Where did you find the Horcruxes you destroyed?"

"Wait a moment," Ron cut in. "Not to be rude or anything, but- Harry, are we sure we trust him?"

"Ron!" Hermione hissed, eyes wide.

"Look, the Black family is bad news," Ron insisted. "Sirius was fine, but you've seen the house, and you've seen the painting of his mum. My dad's mum was a Black, and she was blasted off the family tree for marrying a blood-traitor Weasley. And Sirius told us his brother was a Death Eater who bought into everything their parents said. Are we sure we trust him?"

"Regulus changed," Harry said. "He tried to take down Voldemort."

"So he says!"

"Dumbledore believed him."

"Dumbledore trusted Snape," Ron said, then winced when Harry flinched. "I'm not trying to be an arse, but-"

"Among the Death Eaters," Regulus said quietly, "doing anything to one's Dark Mark is tantamount to apostasy. It is absolutely forbidden to alter it in any way."

All eyes turned to Regulus. Slowly, looking like it pained him to do it, Regulus pulled up his left sleeve.

The cut was an ugly one. Clearly, Regulus had done a bit of healing, but not too much. Harry was sure the cut could be healed without leaving a mark, but if Regulus left it as it was, it would leave a ropy scar that would slice right through the center of the Dark Mark.

"Why did you turn against You-Know-Who?" Ron asked.

Regulus's mouth twisted, a quick spasm across his face. Harry thought he'd refuse to answer, but instead, his shoulders slumped just a little, and Harry recognized it as a sign of surrender.

"We ought to sit for this. It's not a short story."

Hermione flicked her wand, and four comfortable-looking chairs appeared around the fireplace. Harry, who'd been wondering if they'd have to sit on the floor, sank into one gratefully. The others followed suit, Regulus sitting tentatively, like he was afraid the chair might swallow him up.

"Well?" Ron asked.

"Ron, please," Hermione hissed.

"He has every reason to distrust me," Regulus said, his voice carefully even. "Everything he said before was true. My family is known for their use of the Dark Arts and their belief in pure-blood supremacy. My parents did their best to instill their values on myself and my brother." Regulus's lip curled. "Obviously, they failed with him, which made them tighten their grip on me all the more."

Harry watched Regulus, waiting patiently for the story. He wouldn't have demanded it, not like Ron did, but he couldn't fully blame Ron for reacting like he did, and he did want to know. Regulus had been a Death Eater, and they'd just been betrayed by someone else they thought was a reformed Death Eater. Making Regulus prove his commitment was the smart thing to do.

"When I was nearly fifteen, Sirius ran away from home," Regulus began. "It was the summer after my fourth year at Hogwarts, his fifth. My parents did everything they could to bring him home, but he ran off to the Potters, and they were an influential enough family that they were not easily cowed. When my parents accepted that Sirius would not come back, they disowned him and made me their heir." Regulus's face twitched, like he was trying not to make a face. "There were certain… expectations that came with being the Black family heir. My cousin Bellatrix was already working her way up in the Dark Lord's ranks. Narcissa was married to the Malfoy heir, who was equally ambitious. The Black family is interwoven with nearly every pure-blood family in Britain, and many of them were also supporting the Dark Lord. As the Black heir, I was expected to do the same."

"Why didn't you leave with Sirius?" Hermione asked. When all eyes turned to her, she looked a bit embarrassed, but continued, "When he left. He said your parents were awful, and when you knew what they wanted, why didn't you run?"

Regulus looked down at his wand, which he was twirling between his fingers. "They were my parents," he said quietly. "I was never as rebellious as Sirius, so they weren't quite as harsh with me. And I-" He pressed his lips together for a moment. "When we were young, I do think Sirius mostly believed them. Perhaps he had some reservations, and he and my mother always butted heads, but I don't think he recognized how awful they were until he was sorted into Gryffindor and was surrounded by people with a different perspective. I was sorted into Slytherin." His mouth twisted. "I was warned that my parents would not tolerate another diversion from the family's usual tendencies. The Hat did consider placing me elsewhere, but I knew what the consequences would be if I went anywhere but Slytherin."

"But why did you stay?" Hermione repeated, looking confused. "Once Sirius ran and you knew you could-"

"They were my parents," Regulus repeated. "I didn't have friends like Sirius did, who would take me in. I didn't have anywhere to go, and even if I had, I was never the rebellious one. I wouldn't leave. I- I don't hate everything about my family. I am proud to be a Black. I didn't want to throw that away. And even if I'd tried, I don't think my parents would have let me go. There were only two of us, and someone had to be heir."

"It's not that easy, Hermione," Harry said quietly, thinking about life with the Dursleys. He'd never really tried to run away, even before he knew about the protection his mother's blood offered him so long as he lived with his aunt. He'd thought about it, but it had never seemed like something he could actually do. He could imagine it had felt the same way for Regulus, even after Sirius left.

"So your mum and dad supported You-Know-Who?" Ron prompted, clearly trying to get back on topic.

"They never openly said as much, but all the old pure-blood families did," Regulus said. "At least, the ones who cared about blood status did, and that was most of them. There were some exceptions, but most of the old families were either supporters of the Dark Lord or at least not opposing him. My family supported him, but only among others we knew were supporters. The goal was never to do anything incriminating, just in case. Mother was pleased to hear about the masks, but she thought the Dark Mark was foolish. The Dark Lord insisted, however, and so it was arranged that I would receive one."

"Did you… want one?" Harry asked tentatively.

"Well, I did agree with my mother that a permanent tattoo was a foolish choice, in case the Dark Lord lost," Regulus said dryly. "I… I had been taught that Mud-" He caught himself. "Muggle-borns were inferior to pure-bloods, but I never felt comfortable with the idea of killing them. The thought of subjugating Muggles…" Regulus shook his head. "It wasn't that I liked the idea of ruling them, exactly, but the thought of being able to live openly without having to hide in public was appealing. Of course, my family spent little time with Muggles, but when you live in the center of London, it's difficult to avoid them entirely. The Dark Lord told us we would no longer have to hide. That had a certain appeal."

"So you supported him?" Ron asked.

"I had little other choice," Regulus replied. "There were certainly some aspects of the Dark Lord's plans I found… distasteful. There were other parts I didn't entirely disagree with, but it didn't matter. Cousin Bella spoke with my parents, and then she made overtures to the Dark Lord, and by that point, it was too late for me to say anything."

"Why didn't you refuse?" Hermione asked. "Or join the Order?"

"I did not disagree with the Dark Lord's ideals enough to die for it, and by the time I was made aware of what was being prepared, that would have been my only other option."

"But you changed your mind later," Harry pointed out. "You almost did die going against Voldemort."

Regulus looked down at his wand. "Circumstances changed. When I first joined, I was only sixteen, so there was little I could do. I was supposed to help recruit students at Hogwarts, but I was quiet and studious, and the fact that I was on the Quidditch team still wasn't enough to make me truly popular. Others had more luck with that. Once I came of age, though, things… changed. The Dark Lord began asking more of me. I began going out on missions with the others. We went up against the Order a few times. It was more than I felt comfortable doing, far more than I wanted to do, but… I think the Dark Lord may have been able to sense it, or at least he knew I was less enthusiastic than he thought I ought to be. There was little he dared to do openly, seeing as I was the Black heir, but I could tell he was displeased. As he grew in power, I suspected he would dare more. I was not yet ready to go against him." Regulus took a deep breath. "So when he asked to borrow someone's house-elf, I made sure to be the first to volunteer mine."

"Borrow a house-elf?" Hermione and Harry asked in accidental unison.

"Why?" Hermione asked.

"I didn't know," Regulus replied. "I told Kreacher to go with the Dark Lord, do everything he said, and then return home and tell me what had happened. He went off one night, and when he came back…"

Regulus's hands were shaking, Harry noticed, just barely. Apparently noticing that Harry had noticed, Regulus tucked his hands away in his sleeves, gripping the cuffs tightly.

"Kreacher came back soaking wet and pained. It took some time, but after he recovered, he told me what had happened. The Dark Lord took him to a cave, and he made Kreacher drink a potion, and then he put something in the bottom of the basin and left."

"He left?" Hermione repeated, sounding outraged. "He just left Kreacher there?"

"Of course he did, Hermione, he's You-Know-Who," Ron dismissed. "What else were you expecting?"

"He underestimated Kreacher," Regulus said wryly. "There were spells in the cave that prevented Apparition, but only for wizards, not for house-elves. Kreacher was able to escape, and when he told me what happened…"

The story seemed to be fracturing somewhat. Harry couldn't blame Regulus for losing focus as he neared the end, so he tried to prompt him with a question. "How'd you know it was a Horcrux?"

"The Dark Lord had made comments before about immortality," Regulus said. "Nothing specific, but there are only so many ways to make oneself immortal. I knew he wouldn't want anything he couldn't do entirely himself. The Dark Lord trusts no one. Making a Horcrux seemed like the sort of thing he would do. He said a few things that made me wonder if he'd made more than one, but I hadn't thought that was possible."

"So you knew about the Horcrux, and you decided to destroy it?"

"The Dark Lord is not the sort of person who should be immortal," Regulus said simply. "And I… I could no longer stomach doing the things he asked me to do, and doing them for him. Going after the Horcrux seemed a clean way of… ending things."

"So…" Ron said slowly, "you went to the cave, and Kreacher took the Horcrux, and you've been asleep or whatever there for the past… How long did you say, Harry? Eighteen years?"

"I went into the cave in 1979," Regulus said quietly. For a moment, he was silent, then he added, "I… I am aware that I did inexcusable and unforgivable things. I am not asking for you to forgive me. I'm not even asking for you to trust me. I'm asking for you to let me help you. The Dark Lord needs to be defeated. I want to help defeat him."

"You were afraid before," Hermione says. "Are you not anymore?"

"Before, I was afraid of what the Dark Lord would do to me, and what he would do to those I cared about. Even after I stopped caring what he would do to me, I still cared about my family." Regulus smiled, but the expression was utterly without humor. "But my family is dead. There is only one person left whom I care for, and Kreacher is already in danger through his association with you. I have no more reason to be afraid."

"So you want to help me?" Harry asked.

"Help us," Ron corrected. Hermione nodded. "Hermione and I are with you, Harry."

"Help us, then?" Harry asked, feeling selfishly grateful that his friends were willing to put themselves in danger for him once again. "I'm- We're going to go after the rest of the Horcruxes. Do you want to help?"

"I ought to finish what I started," Regulus said. "If you will have me, I'll go with you."

Harry looked at Ron and Hermione. He could see the acceptance and agreement on their faces, so he turned back to Regulus.

"Then we should probably start planning what to do first."

Regulus's smile seemed a bit more real this time around. "I suppose we should."