As Harry approached the Shrieking Shack, he pressed a large button with a red X over a drawing of an ear. The engine fell silent, but continued to run. The clearing was quiet below them.

"Harry, I don't think we should be doing this."

"Why not? If we catch Pettigrew, it's easy to prove Sirius's innocence. And you'll get your wand back."

Hermione frowned and made a small noise in her throat. "Mmm. Fine. But keep your voice down, otherwise we'll hear ourselves."

"I think the other me will be too busy with a werewolf to worry about strange voices outside," Harry said.

Below them, there was a muffled shout—past-Harry's voice. "Hermione, look out!"

Harry pulled his wand and aimed at the window. "Try to petrify him immediately. Don't let him get far." Hermione grimaced, but drew Ron's wand and took aim.

Below them, a boarded-up window blasted open. Harry felt his palms begin to sweat. Inside the shack, out of sight, Pettigrew was moving toward the window at this very moment. He was almost ready to make his escape… there. A small shape shot out of the window—Peter Pettigrew, the rat.

Harry and Hermione began casting. "Petrificus totalus. Petrificus totalus." Their spells struck the ground on either side of the rat. Pettigrew raised his head briefly, identifying the location of his attackers, then made a mad dash to toward the edge of the forest.

Harry continued casting petrifying charms, but the rat was too small and too nimble. Pettigrew was impossible to hit. Harry and Hermione were casting as rapidly as they could, but they had no chance of petrifying Pettigrew

Inside the shack there was a sudden loud snarling and barking—Black had transformed and was now fighting with Lupin. Harry took advantage of the commotion, and tried a new tactic.

"Incendio!" A fist-sized fireball rocketed out of Harry's wand and exploded against the ground near the rat. Pettigrew squeaked and dove away from the fire. Harry's spell hadn't come any closer than before, but the splash of flames from the impact had almost caught Pettigrew. The rat scrambled to his feet, taking a second to get his bearings before he resumed his desperate dash for the forest.

"What are you doing?" Hermione asked. "I thought we were capturing him!"

"We'll never petrify him at this distance," Harry said. "I'd rather have him dead than free. Incendio!"

Inside the Shrieking Shack, past-Harry's voice called out. "Black, let's go!"

Harry's curse missed again. Hermione continued to cast petrifying charms, but she was no more accurate than Harry and Pettigrew was quickly approaching the edge of the trees. Harry remembered something that Hermione had said a few hours ago: "The anti-apparition wards end just past the Shrieking Shack." If Harry was ever going to stop Pettigrew, he had to do it now.

Harry began waving his wand in a circle above his head. "Incendio. Incendio. Incendio." A fireball appeared at the tip of his wand. Each time Harry circled his wand, he repeated the curse, and each time Harry repeated the curse, the fireball grew, first the size of a fist, then the size of a bludger, then the size of a melon.

"Harry, what is that?" Hermione yelled.

Harry ignored her. He could feel the heat coming off his curse; the fireball was now as big as one of the tires on the motorcycle. Below, Pettigrew was almost to the edge of the trees. It was now or never.

Harry snapped his wand down, and cried out one final time. "Incendio!"

The massive fireball roared toward the ground, illuminating the clearing in brilliant reds and yellows. If Pettigrew could sense the danger, he didn't look up—he continued his sprint toward the trees and the edge of the anti-apparition wards.

The fireball struck the ground and detonated in an enormous explosion, and the force of the blast shook the Shrieking Shack. Harry saw flames rise upwards, and raised a hand to cover his face. As the heat began to fade, he lowered his hand and looked at the clearing.

The meadow was devastated. The grass, green only moments before, was now black and charred. Some small trees had been blown completely over, and small fires burned in several places.

There was no sign of Pettigrew.

"I'm going down to look," Harry said.

"Harry… nobody could have survived that."

Harry laughed harshly. "I've read that news story before, Hermione. I have to know."

Harry brought the bike down in the center of the clearing. He hopped off and began walking around, searching the ground for any sign of Pettigrew's body. Hermione immediately moved in the opposite direction. When she reached the Shrieking Shack, she cast reparo, restoring the boards to the window. No werewolf would be roaming the Forbidden Forest tonight.

Harry ignored her, focusing on the ground at the edge of the woods. As he scanned the ground, Hermione moved around the meadow, casting aguamenti and putting out the fires that were still burning.

Finally, Hermione approached Harry. "It's getting late, Harry. We have to go. Did you find anything?"

"No." Harry's voice was bitter. "That rat escaped again."

"Harry… there's no way..."

"If there's one thing that Pettigrew does well, it's run away," Harry said. "He's still out there, somewhere. I can feel it." Harry turned to Hermione, his face hard. "I'm going to find him. And when I find him, I will kill him."

Hermione drew back. The cold hatred in Harry's voice was frightening.

"Let's go," Harry said. "We can still make it to the lake." Harry's tone left no room for protest. Hermione followed Harry to the bike and climbed into the sidecar. Harry started the engine and lifted them into the air, smoothly taking them above the trees and across the forest.

*!*!*!*!*

As Harry approached the lake, he could already see flashes of light from his past self's patronus shield. He landed on the opposite side of the lake, quietly setting the bike down among the trees. He walked quickly toward the shore.

"It was just over here," Harry said, pointing at a log ahead of them.

"Stay back," Hermione said. "You don't want to see yourself."

Harry nodded absently. It was several seconds until the full import of Hermione's words struck him. Harry's heart sank, and he lowered his eyes to the ground.

"It wasn't my dad," Harry said quietly.

"What?"

"It was me," Harry said. "I look just like him, remember? I didn't see my dad. I saw myself." The assertiveness and anger from earlier were totally gone from Harry's voice.

Hermione reached out and touched Harry's arm, gently. "I'm sorry, Harry."

"I knew it couldn't be him," Harry said. "But I hoped. I wanted to see him, for real. Just once." Harry looked across the lake and saw that his past self was beginning to collapse. "This is my cue," he said, standing.

As Harry walked toward the log he thought of Ginny Weasley, but it wasn't enough to free his heart from despair. Everything that he had believed for the past year was a lie. Tonight, he had let his father's killer escape, twice. And on top of it all, the vision of his father was nothing other than the same image he saw in the mirror every morning. Harry felt like he had nothing left. Nothing would ever make him feel happy again. He couldn't cast a patronus feeling like this. Why would he even try? What was the use of going on?

Pettigrew.

The thought came from nowhere. It felt foreign, like when the Sorting Hat spoke directly into Harry's head. Pettigrew was still out there.

Harry's imagination burst to life. He could see Peter Pettigrew, wandless and kneeling in front of Harry. Pettigrew's hands were shaking and his lower lip was blubbering up and down. He was begging for mercy, and Harry would grant it to him—the same mercy that Pettigrew granted his parents, the mercy of death.

Harry smiled wickedly.

Across the lake, past-Harry's patronus shield finally failed. The dementors moved close, drawing back their hoods.

Harry stepped forward onto the log and raised his wand. "Expecto patronum!"

Two enormous prongs burst from the tip of Harry's wand, followed by the body of Harry's fully corporeal patronus. The white-bodied patronus shot across the lake, scattering the dementors and smoothly sweeping them away from past-Harry and Black. The patronus reared up and shook its head at the dementors, as if challenging them to a battle.

When it was clear that the dementors would not return, the patronus slid back to Harry, stopping just short of the Slytherin wizard.

"Harry?" Hermione had moved forward and was now standing by his side. "Your patronus… that's… that's a basilisk."

Harry hadn't moved from the moment that the patronus had left his wand, fangs first. The enormous serpent was so bright that it was almost blinding. Its beautiful ivory scales glittered with internal radiance, a shimmering opalescence that shifted and moved in the moonlight. As Harry and Hermione watched, the patronus closed its eyes, bowed to Harry, and then slowly dissolved into the air.

"Why is your patronus a basilisk, Harry?"

Harry snapped out of his reverie. It was a basilisk because Harry had claimed the title of Heir of Slytherin, of course. But he hadn't told Hermione that. Couldn't tell her that. She was muggle-born, and had been attacked last year. Better not to explain.

"It wasn't a basilisk," Harry said. "That was a boa constrictor. I set one on my cousin Dudley, accidentally, the summer before we came to Hogwarts. That's a happy memory, for me."

Hermione put her hands on her hips. "That was no boa constrictor, Harry."

Harry turned and looked Hermione directly in the eye. "Yes, it was. And if anybody asks, that's what we'll say. People already think I'm going dark because I'm a parselmouth in Slytherin. If my patronus was a basilisk, then a whole mess of problems would open up for me. So it's a good thing that my patronus is a boa constrictor, RIGHT?" Harry's teeth were gritting together, and his hand was clenched tightly around his wand.

Hermione leaned back and raised her hands slightly, palms out. "Okay, Harry."

"Good." Before Harry could say more, he heard voices across the lake. He grabbed Hermione and pulled her down, behind the log that they had been standing on.

Dumbledore and Hagrid emerged from the forest across the lake. Hagrid was the first to speak.

"Sirius Black! That's why there were so many dermenter's, Professor! And Harry! I knew we shouldn't'er left 'em behind!"

"Curious," said Dumbledore. "But I can reach no other conclusion. Please take Harry to the hospital wing, immediately. I will lock Sirius Black in the Astronomy Tower until we can contact Minister Fudge and announce his capture."

"But Professor, what about Hermione?"

Dumbledore shook his head. "If Ms. Granger has suffered any harm, it has unfortunately already occurred. We must focus on helping Harry, and keeping Sirius Black restrained. Can you do it, Hagrid?"

Hagrid nodded sadly.

"Thank you," Dumbledore said. "Now, quickly. Off you go with Harry."

Hagrid lifted Harry's body off the beach and dashed into the woods, taking long, rumbling steps. Dumbledore drew his wand from his cloak cast a quick spell to lift Black's body into the air. He paused and took one last look around the lake, then moved into the forest himself.

"Okay," said Harry. "It's easy from here. Black hops onto the bike, and we're all free."

"Sure thing, Harry," said Hermione.

By the time Harry and Hermione reached the Astronomy Tower on the motorcycle, Black had regained consciousness. He was pacing around the Astronomy Tower like a caged animal. Harry called to him in a stage whisper. "Black! Black, come to the window!"

Black moved to the window and broke into a large smile. "Harry! Thank you for coming for me. And on my old bike, no less."

"Get in, we don't have much time!" Harry said, waving at the sidecar.

"What do you mean, 'My old bike?'" Hermione said.

Black climbed out of the window and into the sidecar. "I gave this bike to Hagrid on Halloween thirteen years ago," Black said. "He used it to take Harry to Dumbledore while I went after Pettigrew. The sidecar made it safer than any broom."

Harry pulled the motorcycle away from Hogwarts and raced toward the Forbidden Forest. In moments they were safely concealed by the trees, far away from the prying eyes of the Minister of Magic. As soon as the motorcycle was safely stopped, Hermione was off the bike and on the ground.

"I don't know how to thank you," Black said as he climbed out of the sidecar.

"Stay safe," Harry said as turned off the motorcycle, then climbed off the seat. "We have business to conduct. We might not be friends yet, but I can't think of another person who would want to kill Pettigrew as badly as I do."

Black chuckled. "Hopefully we will find more common ground than our mutual hatred of that rat, Harry." Black threw his leg over the motorcycle seat. "Do you mind if I write you?"

"Of course not," Harry said.

"Good." Black started the motorcycle and immediately pressed the button with the picture of the ear. The sound of the rumbling engine echoed through the trees. "That's how a bike is supposed to sound," Sirius said with a smile. Black revved the throttle and prepared to take off, then paused and turned to Harry once more. "By the way, Harry: how does the Firebolt fly?"

"That was you!?"

"I told you so," said Hermione.

"Of course it was me," said Sirius. "I bought you your first broom when you were just a baby. I'd never let my godson go broomless, no matter what house he flies for."

Harry felt like his heart was going to burst. This must be what it feels like to be loved.

"It flies like a dream," Harry said.

"Smashing." Sirius waved a hand. "So long, Harry."

Harry raised a hand in reply. "Bye."

Black gunned the engine of the motorcycle, and a moment later he was gone in the night.

Harry looked at Hermione. "Maybe he's not that bad, after all."

"Told you so," said Hermione.

"Stop saying that," Harry replied. He turned back toward Hogwarts, then gasped. "Hermione! We have to get back to the hospital wing! We're almost out of time!"

"How are we going to make it?" Hermione asked.

Harry shrugged. "We run."

Harry started off at a jog, and Hermione sprinted to catch up with him. Harry led Hermione on a mad dash through Hogwarts, down two secret passages and up several flights of stairs. The two young wizards were out of breath when they reached hallway leading to the hospital wing. Dumbledore was just pulling his head from the doors of the hospital wing and closing them behind him.

"Professor," Hermione said quietly. "We're back."

"Ah, good evening Ms. Granger, Mr. Potter. I trust that you were successful in this evening's endeavors?"

"Yes, sir," said Harry.

"Excellent. And I believe…" Dumbledore pressed his ear against the door of the hospital wing. "Yes, I believe you have gone. Into the hospital wing with you." Dumbledore opened the doors and ushered Harry and Hermione through.

"What about the Minister?" Harry asked.

"I will deal with Cornelius," Dumbledore said. "Your greatest concern should be getting a good night's sleep. We will speak at length in the morning, I am sure." Dumbledore closed and locked the doors behind him.

Harry looked at Hermione. She was still gasping for air.

"How am I supposed to sleep after that?" Harry asked. He was exhausted, true, but another part of him wanted to stay awake for the whole night. And if he had to talk to Hermione the whole time, well, that wouldn't be a terrible thing. He gave Hermione a hopeful smile.

"I don't know about you, but I'm going to go pass out from exhaustion," Hermione said. She wasn't looking at Harry, though; she was looking at Ron. "And we have an exam tomorrow. You can stay awake, but you're on your own." Hermione flopped down on the nearest bed and immediately closed her eyes.

Harry's heart sank. He slowly walked back to the bed he had left several hours—seconds?—ago, and lay down as well. He closed his eyes and tried to clear his mind. He tried not to think about the sound of Hermione's breathing, which sounded suspiciously as if she were still awake. Eventually, physical exhaustion overcame Harry's racing mind, and he began to drift off to sleep. As the room went dark, Harry heard Ron softly mumbling from across the hospital wing: "Roontail Wazlib…"