‘Rebecca,’ I said. Different voice, direct and serious. ‘There are going to be things I can’t tell you. And I’m going to sit here asking you to tell me everything you know just the same. I know that’s unfair. But if Holly’s ever said anything about me, I’m hoping she’s told you that I’m not going to treat you like an idiot or a baby. If I can answer your questions, I’ll do it. Give me the same respect. Fair enough?’

You can hear when you hit the right note, hear the ring of it. Rebecca’s chin lost the stubborn tilt; some of the wariness in her spine shifted to readiness. ‘Yeah,’ she said, after a moment. ‘OK.’

Conway quit messing with her Biro. Sat still, ready to write.

‘Grand,’ I said. ‘So. Who left the art room?’

‘Julia went back to our room, to get one of our old photos that we’d forgotten. I went to the toilet; I think so did Selena. Holly went to get chalk – we ran out of white, so she went and got more. I think from the science lab.’

‘Do you remember what times? What order?’

Rebecca said, ‘We were in the building the whole time. We didn’t even go off this floor, except Julia and she was only gone like a minute.’

I said gently, ‘No one’s saying you did anything wrong. I’m only trying to work out what you might have seen or heard.’

‘We didn’t. See or hear anything. Any of us. We had the radio on, and we just did our project and then went back to the boarders’ wing. And we all left together. In case you were going to ask.’

Spark of defiance in there at the end, chin going up again.

‘And you gave the key back to Miss Arnold.’

‘Yeah. At nine. You can check.’ We would. I didn’t say it.

I took out the photo.

Rebecca’s eyes hit it like magnets. I kept it facing me, did the flip back and forth against a fingertip. Rebecca tried to crane her neck without moving.

I said, ‘On your way here last night, you passed the Secret Place. You passed it again on your way to the toilet and back. And again when you left at the end of the evening. Right?’

That pulled her eyes away from the photo, back to me. Wide eyes, on guard, riffling through wild guesses. ‘Yeah.’

‘Did you stop for a look, any of those times?’

‘No.’

I gave it the scepticals.

‘We were in a hurry. At first we were working on the project, and then I had to get the key back on time. We weren’t thinking about the Secret Place. Why?’ One hand coming out from under her leg, uncurling towards the photo; long thin fingers, she was going to be tall. ‘Is that—’