No, Sirius thought, desperately trying to will the flames back, but it was no good.

Dora screamed, a gut-wrenching, "No! Sirius!" but Sirius had no time to do anything but get a hand up to cover his face from the heat. The dog closed scalding jaws over his arm.

Sirius had a fraction of a second of clarity—enough to notice his robes had caught alight when the dog touched him, enough to smell cooking meat over the smoke and rot in the shack and register that that was him despite the fire-freezing charm from earlier, and enough to think I'm going to lose my arm before there was a screech and several brighter flashes of fire.

Then, Sirius was falling and in such excruciating pain that he wasn't aware of much of all.

Fawkes wasn't quick enough to get to Sirius before the dog, but he got there just after, and Dora hoped it was enough; the dog disappeared, but so did Fawkes.

When Sirius landed, he curled in on himself writhing, which meant he was still alive, at least. His robes were aflame and his wand—still clasped loosely in his fist—continued to dribble fire onto the hearth.

Dumbledore was already moving toward Sirius, water swirling from the tip of his wand, but only to protect them; he'd done nothing about Sirius' wand, and the fire spurting from it was rapidly taking shape again—

"We're close!" Dumbledore called, and Dora let out a gusty breath, doing her best to contain the flames to the hearth with hastily drawn runes and tendrils of water. Scalding water splashed back at her.

The fire formed a second dog, which shook itself, spraying flames everywhere. One of the couches went up with a whoosh and a thick cloud of smoke, and the nearest set of curtains started to glow, and a pile of leaves and muck exploded in orange heat and light.

Dore decided enough was enough:

"Expelliarmus," she cried, and Sirius' wand went spinning across the floor. The fire stopped spilling from it but Dora didn't stop; she spun in a quick circle, conjuring water all around her, then forced it away from her to douse what it could in the rest of the shack.

Steam hissed and spat from where it had made contact with the hound but did nothing to diminish it. It did, however, make the hound turn away from Sirius and Dumbledore—who was kneeling over him—and toward her instead.

Dora's stomach clenched and though the house was like an oven and she was covered in sweat, she felt suddenly cold with fear. The dog fixed its empty, blazing eyes on her, then prowled forward, its snarling jaws dripping fire.

Dumbledore made a noise of triumph, and something flared on the hearth, bright as the Fiendfyre; the rune, she realised distractedly, but she had more important things to worry about—namly, the dog, which was prowling toward her.

She lifted her wand and braced herself.

The moment its glowing paw moved off the hearth and touched the floorboards, however, it disappeared as suddenly and completely as a candle being snuffed… and so did everything else.

Albus wasn't sure what specifically triggered Tom's Fiendfyre defences but it was clear something had, because the dog vanished at the same time as cold magic surged through the floor, plunging everything into a darkness so complete Albus could not see the spectacles on his nose. His eardrums burst painfully and tears sprang into his eyes.

The air was dragged from his lungs in a whoosh, and when he tried to breathe, he could not. He was suddenly freezing, though the room had been sweltering less than a second before. Beneath his hand—for he could no longer see Sirius, only feel him—Sirius convulsed.

He started to struggle against Albus' grip—perhaps panicking, perhaps just trying to get free so he could feel his way to his wand, which Nymphadora had hit out of reach. Albus summoned it and felt his way down Sirius' arm so he could press it into his hand; two wands were better than one.

Albus tried to breathe again and failed; he lifted his wand to his mouth and thought, Ventus.

Nothing happened.

He frowned and attempted to transfigure whatever was around them into air instead, and had no luck with that either.

Albus felt the first stirrings of proper fear, fear that without having prepared for what they were up against, that they might have taken on too much, might have risked too much.

He pushed that aside in favour of looking for solutions, and, while the cold was a problem, it wouldn't kill them before the lack of air did, so he ignored it. He considered and dismissed a modified bubblehead charm; one had to be able to breathe to use one, and his lungs were empty.

We leave, then, he decided, clenching his teeth so he wouldn't shiver in the frigid air (or lack thereof). And try again in a few minutes. Though, in truth, that would depend on how badly hurt Sirius was, and on how Nymphadora had fared since the darkness fell.

He gripped Sirius more tightly and spun on the spot, thinking of a place on the road outside, but the blackness pressed in, restraining him.

They didn't move—or, if they did, it was impossible to tell through the dark.

His chest was beginning to feel tight and his head both light and like it was going to explode all at once. He pressed his wand to his chest, focusing on his heart and a steady rhythm, as slow as he could make it without rendering himself unconscious.

Ba-dum, went his heart, and he shivered in the cold air.

Beneath his hand, Sirius shivered once, then went limp and did not respond when Albus squeezed his shoulder.

Albus could do nothing for him, not without compromising himself, and if Nymphadora had already succumbed then Albus was the only one left. And if he could not devise a way to overcome this blackness, or get them out in the next few seconds, then he would lose consciousness too, suffocate alongside them, as was doubtless Voldemort's intention.

Thoughts whizzed through his mind; that he had no wish to die when there was still so much to do, that he had no wish for Sirius and Nymphadora to die while they were under his protection, that Fawkes would be trapped here with them, unable to die and instead be caught in an endlessly awful cycle of being reborn and suffocating.

Ba-dum.

If they did not make it out, Minerva would alert the Order when Albus failed to return on time, and she would see to Morfin, and to the school, and would ensure Harry and Remus were notified.

And Harry and Remus would come looking, would likely find them, and then, in all likelihood attempt to retrieve the horcrux themselves and stumble right into this very same trap.

That would not do. None of it would.

Albus lifted his hand away from Sirius to draw a screen in front of himself, and though he could not see it, he could see through it, see the way the magic on the other side glittered. It was everywhere, and impossibly dense and intricate; it would not be as simple as pulling on one thread of his enchantment and watching the rest unravel, it would need to be unpicked, like a mistake in a knitting project, and Albus had seconds, not minutes or hours.

Well, he thought, when finesse is not an option…

Ba-dum.

Albus lifted his wand. The moment it left his chest his heart sped up—foolish thing—and his eyes burned.

Ba-dum.

There would have been spots dancing before them if there'd been anything other than blackness to see them against, he was sure.

Ba-dum.

The darkness was suffocating, and his chest was painfully tight. There was pressure building in his throat and nose, urging him—begging him—to take a breath. His teeth had begun to chatter.

Ba-dum.

Finite incantatem, Albus thought. It was insanity, perhaps, to think Voldemort's enchantment, meticulously designed and powerfully cast could be made to come undone by something as simple as a general counterspell most first year students knew.

Ba-dum.

The darkness did not vanish, but Albus' counterspell lingered too, pressing against Voldemort's own magic.

Ba-dum.

A wave of dizziness hit Albus and he swayed where he crouched, clumsily throwing out his empty hand to catch himself before he could fall.

Ba—dum.

They were well matched, he and Tom, in terms of magical power; Albus could not see it, but he could feel it—Voldemort's magic working to smother his, and his own magic struggling to find purchase, a place to pierce through Voldemort's darkness.

Ba—dum.

Voldemort's spellwork clever and strong and sophisticated—

Ba—

—dum

—but Albus' was a command given to the Elder Wand by its master.

Draco was grateful for Black's message because it had given Potter something other than Draco and Weasley to focus on. A small part of him, though, was exasperated by it—not that they'd found a horcrux, or that Black had let them know, but his timing; he had enough to worry about that afternoon without adding concern for Black and Lupin to the mix.

But when are we ever lucky enough to have the luxury of a single worry at a time? Draco thought, and snorted to himself. Weasley glanced his way and Draco shook his head.

Potter was practically vibrating in front of them in the seat beside Granger, and Draco was positive he wasn't taking in a single word of Slinkhard's book… not that any of them ever took in much of that drivel anyway.

It was rather cruel of Black, in Draco's opinion, to have sent Potter a message like the one he had, without giving him a location; it meant Potter couldn't do anything but wait, and Potter'd never been particularly good at waiting. Still, a location would have had Potter skiving off Defence to go and help, and Black was never one to put Potter in danger if he could help it.

Probably for the best, Draco thought, then took a breath to brace himself, and raised his hand. Their quiet reading time grew even more silent, and both Potter and Granger turned—perhaps alerted by the room's changed mood—and gave him questioning and warning glances, respectively.

It took Umbridge a few seconds more to notice, and when she did, she narrowed her eyes.

"Yes, Mr Malfoy?"

"I don't understand this whole section on jinxes and counter-jinxes," Draco said. "Slinkhard seems to be suggesting they're just as dangerous as each other, and frankly, I disagree. How can that be true?"

Granger's hand shot into the air, and Umbridge scowled, but ignored her.

"Keep reading, Mr Malfoy," she said, "and it will all become clear—"

"I've finished the chapter," Draco said. "It's not clear." Umbridge straightened, folding her arms. "I was hoping that—as a Ministry-approved educator, and the person who's supposed to be teaching us—you might be able to explain."

"I think Slinkhard just doesn't like jinxes," Granger said, before Umbridge could say anything. Draco hadn't intended for her to interrupt too, but he supposed she couldn't help herself in the face of something factually incorrect. "He completely disregards their defensive applications, and I suspect it's because he's never used one himself; if he had, he'd know that counter-jinxes are properly named, because they do exactly what they're supposed to do, which is counter jinxes. They're not dangerous at all—"

"Five points from Gryffindor, Miss Granger. This is not the first time I have had to remind you that you are not an expert in this subject, and therefore, have no right to decide what in the curriculum is or isn't correct or properly named. We are silently reading this lesson, and I don't want any more interruptions."

"But—" Draco began. Umbridge made a sharp noise and held up a hand. "—you haven't answered my question, Professor."

"Then you can come and see me after the lesson," she said. "And we can discuss it then." Grim satisfaction filled Draco, and beside him, Weasley let out a soft breath. He wasn't sure if Umbridge had figured out what he was trying to do, or whether he'd just managed to provoke her into it. Still, it was the right outcome, so he supposed it didn't really matter. "Chapter fifteen," Umbridge snapped, looking around at the rest of the class. "And," she added, pre-empting Draco's next question, "if you've finished that, move onto the next chapter."

The rest of the lesson passed surprisingly quickly; Draco was too busy playing out variables in his head—both related to Black's situation, and to the conversation he was about to have—to take in any more of Slinkhard's text.

Weasley gave his shoulder a quick squeeze as he filed out, and Granger gave Draco a troubled look:

"Do you want us to wait?" she asked, scowling in Umbridge's direction; Umbridge was standing behind her desk, expectant.

"Don't bother," Draco said. "I'll meet you at dinner." Granger gave a little nod, and hoisted her bag over her shoulder, headed for the door. Potter had already gone, doubtless to go and demand more information from Black via the parchment, and Weasley had gone with him.

"Come here, Mr Malfoy," Umbridge said, once the last cluster of Draco's classmates—Finnigan, Thomas, and Longbottom—had gone. Draco approached the desk, pulling a chair with him as he went. He sat. "Now, what was the meaning of that little disruption?"

"I meant it when I said I have no idea what Slinkhard's talking about," Draco said. "Frankly, I think Granger's right that he doesn't have much idea himself." Her expression contorted. "But it was mainly to try to get the opportunity to talk to you alone."

"About…?"

"What do you think?" Draco asked.

Her expression brightened at once, though she made a rather pathetic attempt to look stern:

"Well," she said, "that's more understandable, I suppose, but you do know that you can always just ask to speak with me, don't you?" She drew her wand and flicked it at the door, then at the walls. "You needn't be disruptive—"

"I have appearances to maintain," Draco said dismissively, and enjoyed the way her expression spasmed.

She opened her mouth, closed it again, and then plastered on a smile and set her wand down on the desk.

"Of course," she said, and he felt like it cost her. "Well, we're quite alone now, so what did you wish to share?"

"You know the contract binding the group?" Draco said.

"Yes," she said cautiously.

"Turns out not everyone is bound by it. Meaning that if you speak to someone who isn't, they'll be able to answer all of the questions I can't."

"Well done, Mr Malfoy," she said, eyes lighting up. She was silent for a few moments, then, "If Potter's the leader, I imagine he's one of the unbound ones—" She glanced at him for confirmation and Draco kept his face placidly blank. "—but I doubt we'll get anywhere with him, so—"

"You'll have to try someone else?" Draco finished for her. "Yes, probably."

"Where should I start?" she asked. "With—"

"I can't help you there," Draco said, not bothering to look too contrite about it. "I am bound by the contract, remember? That's the whole problem here."

"I confess, I now find it somewhat curious that you are," Umbridge said, watching him closely. "If Potter has made exceptions for others, why not for you? You spend a lot of time together… I'd have said you were close—"

"We're friends," Draco said. "But I'm sitting here, having this conversation with you anyway, aren't I?"

"So you are," Umbridge said consideringly. "Can you allude to who it is? Or perhaps rule out who it isn't?"

"Not if it's with the intention of divulging someone's identity," Draco said. She pursed her lips. "I'm sure you'll be able to work it out; it's someone close to Potter—and that's a fairly limited pool as it is. Someone he trusts, obviously… someone he'd sorely miss if they weren't around."

Draco wasn't sure it was possible to be more overt than that, what with a direct reference to the very-public-and-not-too-long-ago third Triwizard task, but though Umbridge nodded, it was in a distracted sort of a way, and she was frowning thoughtfully.

"I see," she said, and he hoped she did. "Very well, Mr Malfoy. Thank you for your insight; I shall investigate." It was clearly a dismissal, but Draco stayed put. "Is there something else?" she asked, a little impatiently.

"Yes," Draco said, unable to help himself. "Everyone's under the impression that you've kept me back to discuss jinxes with me. I'm quite happy to tell anyone who asks that you have no more idea than Slinkhard, but if you want to answer my question, you're welcome to, and it would be helpful, this being O.W.L. year, and all…"

Though the cold silence vanished immediately, it took time for the darkness to ebb away from the edges of Albus' vision… though he thought that was more due to the fact that he'd been so near to unconsciousness than due to any delay on the spell.

Albus breathed and it had been some time since he'd felt anything so simultaneously wonderful and painful.

He was lying on the sooty floor of the shack, and felt lightheaded, but otherwise unharmed. Sirius was lying beside him, still.

Albus rolled onto his side and tried to push himself upright, shivering, though the air was much warmer again now. His head spun, and feet hurried into his field of vision:

Nymphadora crouched down. She looked perfectly unharmed; gills fluttered on her neck, and her head was surrounded by a large sphere of water, lightly crusted with ice on the outside.

"Ingenious," Albus said faintly. She either didn't hear him, or chose not to acknowledge him, focused as she was on Sirius.

"Rennervate," she said—or at least he assumed so, given her speech was distorted by the water. "Come on, Sirius…"

Sirius gasped into wakefulness, his breathing rapid and desperate and Albus' relief at that was just as heady as his own first breath had been. Nymphadora' rocked back onto her heels, looking distinctly relieved herself, and Albus saw her take Sirius' hand and squeeze.

Soft warmth pressed itself against the back of Albus' hand, and he lifted his head slightly to see a small, grey shape. Something in his chest loosened further; it was Fawkes, reborn, and seemingly unscathed, though the chick was quivering.

Albus shifted gingerly into a sitting position and gathered Fawkes into his hands. Fawkes let out a chirp and Albus ran a fingertip up his beak, taking proper stock of the room.

It was somewhat the worse for wear; the couch was scorched and the walls were blackened in places. Grey ash and a light frost covered the floor—where leaves and other detritus had burned—here and there, and far more prevalently, were patches of now-melting ice where either Albus or Nymphadora had conjured water to put out spot fires.

The hearth was unscathed, and though the rune had stopped glowing—likely when Voldemort's defences triggered—it seemed their hard work had not been for nothing; it now protruded from the stone like a particularly ornate handle.

Sirius sucked in a sudden breath and curled himself around his burned arm, and Nymphadora hastily released him. She said something indecipherable, then made a face; her sphere of water vanished and her gills faded back into her neck.

Sirius was upright himself now, and swearing with impressive fervour and imagination.

Albus had had a glimpse of the damage before, but he'd been distracted by trying to extinguish Sirius and keep an eye on Nymphadora and the Fiendfyre. Now, he was able to see the true extent of the damage.

It was a bad burn, and ugly; where each of the dog's flaming teeth had made contact with Sirius' skin was a black hole, and several of them were deep enough that Albus thought he could see bone. The skin around each of those was waxy and weeping and looked excruciating.

Nymphadora let out a few curses of her own, and reached for him, then retracted her hand hastily, as if she was afraid she'd make it worse.

"Reckon it'll scar?" Sirius asked hoarsely. There was something that might have been humour in the twist of his mouth, but his face was contorted with pain.

Albus shook himself and conjured a sleeve of cold water around Sirius' arm—Sirius went white and hissed—which was all he could do for now:

"Take him to Poppy at Hogwarts," Albus said to Nymphadora. "I will retrieve the horcrux—"

"Alone?" Nymphadora asked, frowning as Sirius let out a pained short and said, "Fat chance." Nymphadora shot a nervous look at Albus.

"Madam Pomfrey's brilliant, but there's not much she can do for Fiendfyre burns," Sirius said raggedly. He sucked a breath in through his teeth. "There's no Fawkes to help this time, either." He nodded at Fawkes, tiny and grey in Albus' hands; Fawkes had been able to help heal Harry's Fiendfyre burn after the fourth task—and even then, only to a point—but that would not be possible for Sirius. Sirius shifted and winced, and Nymphadora reached for him, then dropped her hands again, helpless. "This won't kill me, it just hurts like an absolute—" He broke off, cursing and groaning. "Let's just… maybe be quick from here… though I think you might have to do the Fiendfyre this time, Dumbledore—"

"That won't be necessary," Albus said, and nodded at the raised rune. He smiled at the look of surprised relief on Sirius' face. "You did well." And he had, though Albus was not particularly surprised; Sirius had always had the potential for darkness, more so than either of the Potters—though Harry himself certainly had it—more so than Remus despite the fact that he was, technically, a dark creature, and even more so than Peter Pettigrew, though he'd since proven a quick and capable learner.

"Thanks, I think," Sirius said, wryly. "Although it wasn't— deliberate by the end."

"Nonetheless," Albus said. "You did what I believe neither myself or Nymphadora could have." Nymphadora did not have the makings of a dark witch—it would go against her very nature—and Albus, while knowledgeable about dark magic in principle—and especially how to counter it—had never personally dared dabble in anything truly dark for fear of what might happen; he had too much power to risk losing control, but more than that… he was a little afraid of what might happen if he did discover a propensity for it.

Some things were better left a mystery.

Albus pushed himself to his feet and conjured his magic-seeing screen again; the space beneath them was almost empty of magic now—he hadn't just contained Voldemort's defences, he'd removed them entirely—which made him suspect that if they'd not triggered it with the Fiendfyre, they'd have had to deal with Voldemort's freezing, suffocating magic anyway.

That it was gone now simplified things, and meant it ought to be quite safe to try the handle on the hearth; the only magic that remained down there was a small, round swirl of black, silver, and green, little larger than a silver sickle.

"Shall we?" he asked.