“There was a person here before,” I said. “Standing at one of the windows. I think it must have been the Strangers’ Room.”

“A person?” Will asked sharply. “Are you sure?”

“Yes. I couldn’t see their face because they were backlit, but there was a clear silhouette.”

“It must have been them,” Will muttered.

“Who are you talking about?”

He only shook his head slightly, so I held the 204photo up, peering at the window, half hoping and half dreading the appearance of that dark figure.

“There!” Will said, pointing at one of the photos on the floor.

I looked down and saw that a blurry face had appeared at a window in the tower, just for a moment. Then it vanished, only to turn up in the photo next to it. The same thing kept happening, as if the person was moving through the photographs somehow. And then, all at once, there was a figure at the window in every photo again, including the one in my hand.

“Don’t look too closely,” Will said quickly. “They don’t want to be seen.”

I knew there was no point asking him who he was talking about a second time.

“If they don’t want to be seen, then why are they looking out of the window?” I asked impatiently. I looked back down at the photo in my hands. “Who are you?” I said. “Why don’t you show yourself properly? I know you’re there.”

My last words had the most extraordinary effect on Will. I heard him suck in a harsh gasp of a breath, and when I glanced at him he looked utterly horror-stricken, as if he’d just seen a ghost. 205The colour had drained from his face so completely that I wondered if he might actually keel over. Then we both heard the tread of a footstep on the spiral staircase, and Will flinched.

“My family must have come back early—” I began.

“No!” Will’s voice was barely more than a whisper. In a few steps, he’d crossed over to me and clapped his hand over my mouth. “No, no, no!” he muttered as he tugged me into the corner of the room.

I shoved his hand away and whirled round to face him. “What the hell are you—?”

“Please!” Will hissed. “Please listen. You’ve got to be silent.”

He turned me round, and I found myself standing so close to the wall that my nose almost touched the peeling plaster, as Will tucked himself in behind me.

“What are you—?”

“Trust me!” Will’s voice was soft in my ear. “Close your eyes, and no matter what you hear, don’t open them or turn round. For God’s sake, do as I say!”