Moody raised his wand again, pointed it at the spider, and muttered, “Crucio!”

At once, the spider’s legs bent in upon its body; it rolled over and began to twitch horribly, rocking from side to side. No sound came from it, but Harry was sure that if it could have given voice, it would have been screaming. Moody did not remove his wand, and the spider started to shudder and jerk more violently—

“Stop it!” Hermione said shrilly.

Harry looked around at her. She was looking, not at the spider, but at Neville, and Harry, following her gaze, saw that Neville’s hands were clenched upon the desk in front of him, his knuckles white, his eyes wide and horrified.

Moody raised his wand. The spider’s legs relaxed, but it continued to twitch.

“Reducio,” Moody muttered, and the spider shrank back to its proper size. He put it back into the jar.

“Pain,” said Moody softly. “You don’t need thumbscrews or knives to torture someone if you can perform the Cruciatus Curse . . . That one was very popular once too.

“Right . . . anyone know any others?”

Harry looked around. From the looks on everyone’s faces, he guessed they were all wondering what was going to happen to the last spider. Hermione’s hand shook slightly as, for the third time, she raised it into the air.

“Yes?” said Moody, looking at her.

“Avada Kedavra,” Hermione whispered.

Several people looked uneasily around at her, including Ron.

“Ah,” said Moody, another slight smile twisting his lopsided mouth. “Yes, the last and worst. Avada Kedavra . . . the Killing Curse.”

He put his hand into the glass jar, and almost as though it knew what was coming, the third spider scuttled frantically around the bottom of the jar, trying to evade Moody’s fingers, but he trapped it, and placed it upon the desktop. It started to scuttle frantically across the wooden surface.

Moody raised his wand, and Harry felt a sudden thrill of foreboding.

“Avada Kedavra!” Moody roared.

There was a flash of blinding green light and a rushing sound, as though a vast, invisible something was soaring through the air—instantaneously the spider rolled over onto its back, unmarked, but unmistakably dead. Several of the students stifled cries; Ron had thrown himself backward and almost toppled off his seat as the spider skidded toward him.

Moody swept the dead spider off the desk onto the floor.

“Not nice,” he said calmly. “Not pleasant. And there’s no countercurse. There’s no blocking it. Only one known person has ever survived it, and he’s sitting right in front of me.”

Harry felt his face redden as Moody’s eyes (both of them) looked into his own. He could feel everyone else looking around at him too. Harry stared at the blank blackboard as though fascinated by it, but not really seeing it at all . . .