I paused in front of a room identical to the one I'd been in. Peeking my head around the opening, I couldn't tell who was speaking. A group of four uniformed officers stood on either side of the metal table with their backs to me. My ID wasn't on it. Instead, the bright sides of an un-solved Rubik's cube sat in the center, surrounded by small bills. Oleksa Petrenko slouched in a metal chair. His steel-gray eyes flickered between the gaps in the blue uniforms, finding mine.

"I say no more without my attorney," he said in his brusque Ukrainian accent. The laughter in the room fell silent and four sets of eyes turned to me. I jumped when the door slammed shut.

Walking faster, I checked the next two rooms. At least I didn't have to worry about Oleksa spreading rumors. He didn't talk to anyone, as far as I knew. And obviously, whatever crime he'd committed, including hustling police officers out of their donut money, was far worse than any reason I had for coming in on my own.

I stopped just outside the next door. Lieutenant Nicholson grumbled in a low voice.

"Emily Reinnert's father sits on the city council. He's been all over me for answers and we've got nothing. I want a plainclothes at the play at West River High tonight." I heard the taptap-tap of plastic against the metal tabletop. My ID card. "And I want to keep an eye on this Boswell girl. She knows more than she's letting on. Who do we have inside West River?"

A woman answered. "This is everyone we've got working inside the local high schools." A heavy thud, like a stack of files hitting the surface of the table. A quiet rustling.

"No, I don't want a cop," Nicholson growled. "I need someone who can get in close to the girl without giving Internal Affairs one more reason to crawl up my ass."

"We've got a C.I.-Whelan-at West River," she said. "Sprung him from juvenile about three weeks ago."

A brief silence and a shuffling of papers.

"Wasn't the Whelan kid involved in the shooting at North Hampton?" Nicholson asked.

"We cut him a deal. He stays in school and keeps his nose clean, and in exchange we registered him as a confidential informant. His file says he's got an apartment in Huntington. The kid's parole officer says he's back in school as of this week. She's got him checking in daily by phone. Meets with him on Saturdays."

Nicholson grunted. "And what do we get out of the arrangement, aside from charitable warm fuzzy feelings and another paycheck against my budget?"

"He agreed to help us bust Lonny Johnson."

I held my breath. More papers shuffled in the silence.

"Toss him a bone. Tell him to get in tight with this Boswell girl and we'll expunge the last assault and battery charge from his record. And make sure he stays in line."

"We met with him this morning and debriefed him on the Reinnert case. He's cocky, but he doesn't seem like such a bad kid. Asked him to keep his eyes open in case he hears anything. Lonny's mostly distributing speed and coke, but he'll try to get us something on the local roofie dealers. The lab found ketamine residue in Emily Reinnert's water bottle."

Tap-tap-tap . . .

"I want more than that. I want Whelan to get me everything he can on Nearly Boswell."

I abandoned my ID and crept back from the door.

9.

He wasn't hard to spot. The man in the navy suit came out of the auditorium at least a dozen times during the performance, his jacket buttons straining over something bulky near his waist. He walked to the water fountain without looking at it, eyes roving the hall in both directions as he drank. A thin comb-over flopped in an arc from his head, flirting with the fountain spray when he leaned over. When he stood up, he checked his watch and yawned.

Nicholson had sent one pathetic verge-of-retirement cop, but I guess that's all my skinny prank theory was worth. I'd been observing his unimpressive stakeout for almost an hour from the courtyard. It was the perfect vantage point, dark enough to conceal me, with panoramic views of the halls in each direction. Nicholson was suspicious of me, and I wouldn't add fuel to his fire by flaunting the fact that I was here.

The cop disappeared into the red hues of the theater and I crept back into the hall just as the auditorium doors pulled slowly closed. I withdrew the ad from my pocket. The clue suggested two possible scenarios.

The first-the reference to the play and the invitation to meet up after the show-was an obvious one. Almost too obvious. But the second?

Archimedes knew the play wasn't the thing.

Was the play a decoy? Was the real prank happening somewhere else? Somewhere Archimedes-one of history's greatest mathematicians-would likely be? Do the math . . . I couldn't be in two places at once.

The cop already had the auditorium covered, so I followed my gut to the math department at the far end of the school on tiptoe, pausing every few feet to listen.

I ducked under the stairwell where I could see most of the wing, and since I wasn't sure what I was looking for, I waited. The ad just said "find me after the show." I checked the clock above the fountain. Ten. The show was ending. After the show was now. I squatted low, my breathing shallow. The wing was quiet and still.

The second hand crept slowly over the face of the clock, and each passing second I felt more and more like an idiot for being there. My knees began to ache where they pressed against the cold tile, and a cramp pinched my calf. I shifted positions, stretched my legs, checked the clock again. The whole thing was probably a complete waste of time. I wasn't even sure I was in the right place, or what I would do if I spotted someone, or exactly what I thought they might be doing, but I stayed put, remembering what had happened to Emily. If there was a chance something like that could happen again, I couldn't abandon my suspicion and walk away. I urged the red hand of the clock forward with my mind, wanting to get this night behind me.

By eleven o'clock, I was sure the audience was long gone. The actors were probably washing off their stage makeup and heading to the after-party. The cop was probably shaking his head, chalking the wasted night up to a paranoid girl.

I stepped out from under the stairwell, stretched, and scanned the dark passage. All closed doors.

With the exception of one. Room #112. My AP Physics class.

It was barely cracked, but I kicked myself for not having noticed it sooner. I eased it open, listening. The room was silent. Pitch-black. The hair on my neck prickled.

I reached inside and flipped a switch. The fluorescents flickered to life, turning lumpy shadows into recognizable shapes. Chairs stacked neatly upside down on tables, the blackboard wiped clean, trash can empty.

Everything neat. Nothing out of place. Except one chair.

Mine. It rested on the floor, flipped over as if someone got up in a hurry. I walked over and saw my desk.