The Great Hall was packed to overflowing with students crammed so tightly on the benches they scarcely had room to move their arms. No one seemed to mind the close quarters, though, since they were far more concerned with the piles of meat pies and pumpkin pasties, under whose weight the tables groaned.

For the dozenth time since the feast began, Al glanced toward the entryway, keeping an eye out for Henry. Beside him, Scorpius held an apple tart in one hand and a turkey leg in the other and was tearing into the latter as if he had not seen food in weeks.

"Unh orry. El ee ear," he said around a mouthful of poultry as Al looked at the door again.

"I'm not worried," muttered Al impatiently. "I just wanna get started."

Scorpius swallowed, cheeks turning pink from the effort. "Yeah, me too. 'S a good plan, though. Should go smoothly."

"Should," Al emphasized. "Right now, it's up to Henry, then James, then us."

"Do you know what Lily and Hugo are doing?" asked Scorpius, looking faintly concerned.

Al shook his head. "They're doing it tonight, whatever it is. I just hope th-" He stopped short at the sight of a small red-headed figure strolling casually into the hall. Henry squeezed onto the bench beside James, and the two exchanged a slight nod. Al knew that, beneath the table, James would be pulling his wand and tapping it four times against the stone floor.

Show time.

"Ready?" He leaned over to Scorpius who nodded and shoved the remains of a pastry into his mouth.

For a moment, nothing out of the ordinary happened. Then, slowly, a great clattering sound, growing in volume, began to seep in beneath the roar of voices. Students and teachers left sentences unfinished as their attentions turned to the entrance and the outside hall. Suddenly, the sound stopped, replaced by whispers of confusion. Then, just as suddenly, the clattering resumed, louder this time and in an odd sort of rhythm.

A few students seated near the doors ventured out to investigate. Almost immediately, one of them raced back in and said to the hall at large, "The suits of armour are dancing!"

As one, most of the occupants rose and clambered for the door, Al and Scorpius among them. In the crush toward the line of battle suits performing a jerky can-can, James caught Al's eye and held up both hands, fingers spread. They had, at most, ten minutes before the charm wore off, less if the professors managed to break it. He and Scorpius would have to work fast.

With Scorpius clutching his sleeve, Al pushed through to the edge of the crowd and, with a quick glance backward, ducked around a corner. "Hope there's still some treacle left when we get back," Scorpius said.

"Not like you need it," Al responded, jabbing his friend in the gut.

Scorpius's smile faded, and his shoulders sagged as he shuffled over to a life-sized portrait of a young girl holding a lantern. Pointing at the lantern's dark glass, he muttered, "Lumos," and a soft light spilled out from its slats. Smiling, the girl beckoned him forward as her portrait swung open to reveal a narrow, circling staircase winding right through the spine of the castle.

"Have to thank Henry for that one," murmured Al. To Scorpius, he said, "Best get moving, it's still a ways down to the dungeons."

Scorpius nodded and, as his friend began to move away, called, "Good luck."

Over his shoulder, Al threw back, "You too," and jogged on down the corridor.

Al had never seen the halls so empty. Even late night explorations had been accompanied by roaming ghosts and the snoring of portraits. But now, nearly everyone was at the Halloween feast, and those who weren't, including the portraits, were now making their way toward the Great Hall to see what the commotion was about.

No sooner had he though this, though, than he heard rapid footsteps approaching from the opposite direction. Heart pounding, he darted into a narrow adjoining corridor and pressed himself against the wall. As the steps clattered past, he saw that they belonged to a pair of second years with Peeves hard on their heals and heavily armed with a sack full of rotten eggs. Al wouldn't have been surprised if Lily and Hugo had asked the poltergeist to patrol for them, or even that he had agreed to do it.

Once they were out of sight, he ventured from his hiding place and dashed to rest of the way to O'Brien's classroom. Alohamora made quick work of the locked door, and within seconds he was facing the massive bookshelf behind O'Brien's desk, wand at the ready.

Breathing evenly, he cleared his mind and focused on the sequence that Henry had explained. Once he was sure of it, he aimed his wand at a book in the very centre of the shelf and said in a strong, clear voice, "Diffindo et novo."

For a moment, nothing happened. Then, slowly, the book inched itself out of place on the shelf and hung suspended in the air. In a single, smooth motion, the book's cover pealed away and hovered, detached from its bindings. Immediately, a second book slid from the shelf and also shuffled away from its cover. The two covers exchanged places as a third book joined its companions and switched covers with the second. Another two volumes followed, then three, then five, their binding floating and changing like strange birds fluttering about the office.

Al stared, transfixed, as the spell proceeded through its sequence, too awed to take pride in the complexity of his own wand work. In the seventh cycle, he shook his head, remember that his time was limited, and exited the office.

After a glance at the Map, borrowed from James, to ensure that the way was clear, he hurried back to the Great Hall just as the Prefects were herding their Houses back inside while some of the professors set about returning the suits of armour to their places. He caught sigh of James who arched an eyebrow questioningly. He gave his brother a nod and joined the bustling crowd slowly pouring back into the Hall.

It was several minutes before Scorpius appeared, huffing and flushed, and dropped into his seat beside Al.

"Where'd you come from in a hurry, Malfoy?" asked a seventh year boy, chuckling.

"Loo," Scorpius managed breathlessly. "Thought… might… run out… of sweets."

The other students laughed, and Al, smiling, handed his friend a treacle tart.

The wiser course of action would have been to avoid the various scenes of their crimes and simply allow the chaos to unfold without supervision. But the temptation to witness the fruits of their handiwork was too great for Al. So, immediately after the first class of the day, he and Scorpius raced nonchalantly from Charms, across the castle, to the corridor outside O'Brien's classroom. To Al's surprise, a small crowd had already gathered, Lily and Hugo among them.

He started to ask what was going on, but Scorpius put a hand on his arm. "Listen." Then, Al heard it.

The sounds coming from inside the room were muffled, but there was no mistaking O'Brien's voice shouting franticly over wild crashes and the small screams of his students. Al blanched and turned back to Lily, who was looking unreasonably smug. Hugo, on the other hand, chewed nervously at his lip.

"What did you do?" Al demanded in a whisper, edging closer to them.

"You'll see," Lily whispered back. "The lock sh-"

The door burst open, and through it came a hovering shape, shifting horribly. In the changing form, Al saw a clown's face and a spider's leg and the clawed hand of an old woman. The shifting mass darted about as the crowd of students backed away. Suddenly, it began to spin dizzily. Then, just as abruptly, the blur of motion resolved into the grass-covered mound of a grave directly in front of Lily and Hugo.

For a moment, none of the students seemed to breathe. Then, Lily shrieked as a smooth white hand erupted from the ground and gripped her ankle. Immediately, Al grabbed her shoulders and pulled her roughly away from the grasping hand. Hugo, also, stumbled back, and the grave began to shift and turned on a second year Hufflepuff standing nearby.

Al fought to remember the DADA lesson on boggarts, to remember what shape had confronted him and how he had faced it, but the chaos around him made it difficult to concentrate. The boggart kept spinning from one student to another, changing and terrifying.

"Out of the way! Get out of the way!" shouted a commanding voice from the other side of the crowd. Al craned his neck and saw Neville and Professor Finnegan pushing through the frightened students, carrying a heavy steamer trunk.

The trunk dropped to the floor with a thud, and Neville stepped forward, wand raised. Instantly, the pale vampire twisted into a massive snake sprawling over the stones, its head half-severed in a pool of creeping blood. With one terrible jerk, the snake lifted itself from the ground, jaws snapping as its mangled body swung about unsteadily.

Neville's voice did not waver as he said "Riddikulus," and the snake became a tiny, flopping worm, which Professor Finnegan quickly levitated into the trunk. Only once the lid was shut and fastened did Neville lower his wand.

With a dark look at Lily and Hugo, he dashed into the classroom, leaving Finnegan to handle the frightened students in the hall. As the crowd began to move reluctantly away, encouraged by the arrival of professors Bones and Corner, the first years who had been trapped in the classroom emerged, O'Brien ushering them gently along. Al noticed a few cuts and bruises among the small, pale faces, but his blood ran cold when he saw Neville exit the room, a shivering form cradled in his arms.

Al recognized the girl, a Gryffindor called Marten whose goal in life, James had told him, was to become a professional Quidditch announcer because it was "loads more exciting than football!" Tears streaked her white cheeks, mixing with blood that trickled down from a short gash in her forehead. Her mouth was set in a thin, tense line, and her tiny hand clutched the front of Neville's robes as if her very life depended on it.

Scorpius was deathly pale, and Hugo looked about to be sick. Lily's eyes were wide with shock as she watched the little girl being carried out. Al, though, felt his insides twist into one solid ball and drop down to his feet as Neville cast at him a brief look of chilling, fathomless disappointment.