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"A light, rose-colored mist should be rising from your potion," called Snape.

Only fifteen minutes until Potions class in the cold, drafty dungeon was over. The class was brewing a substance to induce cleverness. Next to Hermione, Harry's potion was raspberry red, and he was stirring frantically. On her other side, Ron's potion was an awful-smelling purple from not being stirred often enough, as he had gone to the loo. Hermione's potion, however, was exactly as Snape had described. They were adding the final ingredients to their cauldrons. Hermione saw a mouse scurrying into a hole in the wall, trying to escape the December cold, and grinned. Snape swept around the room, sneering and commenting. But something was wrong.

The room was suddenly very hot, too hot. Hermione faltered, and couldn't remember what to add to her potion next. She could feel every beat of her heart, and couldn't see out of the corners of her eyes. She stumbled to the door, tried to pull it open. Her arms felt like dead weights. She managed to get outside, but never heard the creak of the door opening. The black in her eyes was spreading. She had to move, had to keep going, but couldn't. Her head was pounding. It was getting more and more difficult to draw breath. She turned the corner, only able to see what was directly in front of her. She saw a black figure moving fast towards her. She felt something cold at the base of her throat. She blinked furiously to try to clear her eyes, but could only see a small window right in the middle. The black covered her eyes entirely, she couldn't breathe anymore. She felt herself falling, but never remembered hitting the ground.

*

Ron walked down the corridor, taking his time to return to the Potions classroom. He heard a terrible, anguished scream. He looked up, and saw Hermione standing there, rigid. His black robes flapped behind him as he sprinted down the hall towards her. Hermione, can you hear me? Hermione! He looked at her face. Her eyes were wide, blank, and glassy. His hands, cold from the winter chill, found her neck, checking for anything that might be strangling her, but found none. She suddenly began blinking very fast, shaking and trembling violently all over. He looked around for anyone nearby, anyone who could help her. She gasped and fell, crumpled. He just barely caught her, calling her name, but got no response. He yelled, and Professor McGonagall came running. He spoke quickly, asking to get Madam Pomfrey, something was horribly wrong. Professor McGonagall took one look at Hermione's limp form, and Ron's stricken face, and sent a silver Patronus streaking off down the corridor towards the Hospital Wing.

*

Ron returned to the Potions dungeon with a minute to go. Ignoring Snape, he sat back down next to Harry, who immediately asked what was going on. All he had seen was Hermione acting feverishly, walking out of the classroom, not responding to him calling her name. In a hollow, scared voice, Ron recounted to Harry what had happened. The bell went, and the boys gathered their things with the rest of the class, shocked.

"You don't think she was being... you know..." Ron said slowly, once they had returned to the common room, "possessed, do you?"