The scream had come from the pretty, freckle-faced student who masqueraded as the team mascot, the Emerson Wildcat, Nancy discovered. The girl was standing behind the bench in tears. She wore the Wildcat costume, minus the head, but it hung from her limbs in tatters.

It had been slashed to ribbons!

“I don’t understand. . . . I only had it off for a few minutes!” the girl sobbed. “I was taking a break, and . . . and when I put it back on . . .” Her sobs grew louder.

“Don’t worry, it isn’t your fault,” the head cheerleader consoled her. “It could have happened to anyone.”

Nancy pushed through the crowd around the unhappy girl. “Excuse me . . . where did you put the costume while you were on your break?”

“In the cheerleaders’ locker room, as always,” the girl said, wiping her eyes with her fingers.

“Was the room locked?”

“No, it never is, as far as I know.”

“Did you notice anyone hanging around in the corridor outside it?”

“No! The hall was empty and so was the locker room.”

“Too bad,” Nancy muttered. Obviously, the practical joker had struck again. She had hoped to gain some clues to his or her identity, but it appeared that none had been left.

Disappointed, she turned away. As she did, she saw that the team members were staring at the damage to their mascot. Their expressions ranged from shock to fear. Probably they were wondering if the next practical joke would involve one of them being slashed, she guessed.

Someone else was looking at the damage, too, she discovered a moment later—Tom Stafford. He was hovering inconspicuously at the edge of the crowd, but thanks to her earlier encounter with him she picked him out right away. Could he have slashed the costume? There was no way to be sure, of course, but the satisfied expression on his face made her very suspicious.