McKenna launched herself out of the common room at Conway’s knock like she’d been waiting behind the door. The long day and the white light in the corridor weren’t good to her. Her hair was still set solid and the expensive suit hadn’t a crease, but the discreet makeup was wearing off, in clumps. Her wrinkles had got deeper since that morning; her pores looked the size of chicken-pox scars. She had her phone in her hand: still doing damage control, trying to patch leaking seams.

She was raging. ‘I have no idea whether your standard procedures involve sending witnesses into hysterics—’

‘We weren’t the ones who kept a dozen teenage girls cooped up all day,’ Conway said. Gave the common-room door a slap. ‘Lovely room and all, but after a few hours the most tasteful decor in the world won’t stop them going stir-crazy. If I were you, I’d make sure they get a chance to stretch their legs before bed, unless you want them going off again at midnight.’

McKenna’s eyes closed for a second on the thought. ‘Thank you for your advice, Detective, but I think you’ve done enough already. The students have been cooped up in case you needed to speak with them, and that will no longer be an issue. I would like you to leave now.’

‘Can’t be done,’ Conway said. ‘Sorry. We need a quick word with Holly Mackey. Just waiting for her da to get here.’

That sent McKenna up another notch. ‘I gave you permission to speak to our students specifically so you would not need to request parental authorisation. Involving the parents is completely unnecessary, it can only complicate the situation both for you and for the school—’

‘Holly’s da’s going to hear all about this anyway, soon as he shows up for work in the morning. Don’t worry: I wouldn’t say he’ll be straight on the phone to the mummy network to pass on the gossip.’

‘Is there any earthly reason why this needs to be done tonight? As you so cleverly pointed out, the students have already had more than enough of this pressure for one day. In the morning—’

Conway said, ‘We can talk to Holly in the main school building. Get us out of your hair, let the rest of the girls go back to the normal routine. How’s the art room?’

McKenna was all monobosom, no lips. ‘Lights-out is at a quarter to eleven. By that time I expect Holly – and all the other students – to be in their rooms and in bed. If you have further questions for any of them, I assume they can wait until tomorrow morning.’ And the common-room door shut in our faces.

‘You have to love the attitude,’ Conway said. ‘Doesn’t give a shite that we could arrest her for obstruction; this is her manor, she’s the boss.’