Harry shivered, then looked around, hoping no one had noticed. Many people had their eyes shut tight. Ron was muttering to himself, "Take its legs off " Harry was sure he knew what that was about. Ron's greatest fear was spiders.

"Everyone ready?" said Professor Lupin.

Harry felt a lurch of fear. He wasn't ready. How could you make a dementor less frightening? But he didn't want to ask for more time; everyone else was nodding and rolling up their sleeves.

"Neville, we're going to back away," said Professor Lupin. "Let you have a clear field, all right? I'll call the next person forward.... Everyone back, now, so Neville can get a clear shot --"

They all retreated, backed against the walls, leaving Neville alone beside the wardrobe. He looked pale and frightened, but he had pushed up the sleeves of his robes and was holding his wand ready.

"On the count of three, Neville," said Professor Lupin, who was pointing his own wand at the handle of the wardrobe. "One two -- three -- now!"

A jet of sparks shot from the end of Professor Lupin's wand and hit the doorknob. The wardrobe burst open. Hook-nosed and menacing, Professor Snape stepped out, his eyes flashing at Neville.

Neville backed away, his wand up, mouthing wordlessly. Snape was bearing down upon him, reaching inside his robes.

"R -- r -- riddikulus! "squeaked Neville.

There was a noise like a whip crack. Snape stumbled; he was wearing a long, lace-trimmed dress and a towering hat topped with a moth-eaten vulture, and he was swinging a huge crimson handbag.

There was a roar of laughter; the boggart paused, confused, and Professor Lupin shouted, "Parvati! Forward!"