"A demon," I told him. "It got into my head a while back. It was causing me to experience… hallucinations, I guess you could call them. I thought I was talking to people. But it was the demon, pretending to be them."

He nodded slowly. "And… and it's gone now? You did, like, some kind of autoexorcism?"

"Not gone," I said quietly. "But it's under control. Once I knew what it was doing, I was able to lock it away."

He peered at me. "Are you crying?"

I turned my face away, trying to make it look like I was staring at the window while I wiped a hand over my eyes. "No."

"Harry. Are you sure you're all right? Not, you know… insane?"

I looked back up at Butters and suddenly laughed. "Look who's talking, polka boy."

He blinked for a moment and then smiled a little. "I just have better taste than most."

I walked to him and rested my hand on his shoulder. "I'm all right. Or at least no crazier than I usually am."

He looked at me for a moment and then nodded. "Okay."

"Good thing you came along when you did," I said. "You tipped the demon's hand when you came up here. There was no way it could fit you into the illusion."

"I helped?" he said.

"Big-time," I said. "I think I'm just too used to knowing more than most people about magic. The demon was using some of my expectations against me. It knew exactly how to hide things from a wizard."

An idle thought flicked through my brain at the words. And suddenly I froze with my mouth open.

"Hell's bells," I swore. "That's it."

"It is?" Butters asked. "Er, what is?"

Mouse tilted his head to one side, ears perked inquisitively.

"How to hide things from a wizard," I said, and I felt my mouth stretching into a wide, half-crazy grin. I dug in my memory until I found the string of mystery numbers and recited them. "Ha!" I said, and threw my hand up in the air in triumph. "Hah! Ha-ha! Eureka."

Butters looked distressed.

"Let's go," I told him, rising excitement making tingles of nervous energy shoot through my limbs. I started walking to give some of it an outlet. "Come on, let's hurry."

"Why?" Butters asked, bewildered.

"Because I know what those numbers mean," I said. "I know how to find The Word of Kemmler. And to do it, I need your help."

Chapter Thirty-six