‘Does that answer all your questions?’

I said, ‘One left. I don’t get why you’d tell me all that.’

‘I’m establishing interdepartmental cooperation, Detective. Showing the love, in a professional kind of way.’ Mackey flicked his smoke onto the ground, crushed it out in one heel-twist. ‘After all,’ he said over his shoulder with a great big grin, as he pushed the door open, ‘we’re working together.’

Holly was sitting where we’d left her; Conway was at the window, hands in her pockets, looking down at the gardens. They hadn’t been talking. The air in the room, the fast turn from both of them when we came in, said they’d been listening hard to each other instead.

Mackey shifted his spot, keep us on our toes: sat on a table behind Holly, found himself a stray chunk of modelling clay to play with. I pulled Selena’s phone towards me. Turned the evidence bag in circles on the table, between my fingertips.

‘So,’ I said. ‘Let’s go back to this phone. You say you found it on the foyer floor, the morning after Chris died. Let’s stick with that for now. You’d seen Selena’s secret phone; you knew what it looked like. You had to know this was it.’

Holly shook her head. ‘I thought it was Alison’s. Selena kept hers down the side of her bed; how would it get to the foyer?’

‘You didn’t even ask her?’

‘No way. Like I told you, I didn’t want to get into that with her. If I even thought about it – and I don’t remember if I did – I would’ve figured, if it was somehow Selena’s phone, then she’d rather go get it out of the lost-and-found than have to talk about how I knew it was hers and all that crap.’

Smooth as butter. No one, not even Frank Mackey’s kid, comes up with that kind of good stuff off the top of her head. Holly had been thinking this through, stuck in that common room with wild things zapping the air. Methodically going through everything we could know, working out her answers.

Some innocent people would do that. Not a lot.

‘Makes sense,’ I said. Behind Holly, Mackey had flattened the clay into a disc, was trying to spin it on his finger. ‘Here’s the thing, but. The way our witness tells the story, you didn’t find the phone in the foyer. You had it tucked down your waistband, wrapped in a tissue.’

Holly’s eyebrows pulling together, baffled. ‘No I didn’t. I mean, I might’ve had a tissue in my hand, everyone was crying—’

‘You didn’t like Chris. And you’re not the type to fake a crying fit for someone you didn’t like.’