‘Well. OK. Gemma thinks her and Joanne run the universe. If she knew something, she probably wouldn’t tell you at all, but if she did, it’d be straight out. With her dad sitting in – he’s a solicitor. So I’d guess Alison. She’s scared of basically everything; if she knew something, she’d never have the guts to go straight to you.’

Holly snatched a glance at Conway, made sure she was writing this down. ‘Or,’ she said. ‘Probably you’ve thought of this. But someone could have got one of Joanne’s gang to put that card up for her.’

‘Would they do it?’

‘Joanne wouldn’t. Or Gemma. Orla totally would, but she’d tell Joanne before she even did it. Alison might. If she did, though,’ Holly added, ‘she won’t tell you.’

‘Why not?’

‘Because. Joanne would be way pissed off if she found out Alison had put up that card and not told her. So she won’t let on.’

This was giving me the head-staggers, keeping it straight who would do what to who if which. Fair play to teenage girls; I’d never have been able for it.

Conway said, ‘If she put it up, we’ll find out.’

Holly nodded gravely. All faith in the big brave detectives, coming along to make everything OK.

I said, ‘What about Chris’s death? Who would you guess was responsible for that?’

I was waiting for the prank-gone-bad story, rattled off nice and neat with Holly’s own fancy twirls on top. Instead she said, ‘I don’t know.’

The clamp of frustration said it was true. ‘Not Colm’s guys messing about, and it went wrong?’

‘I know some people think that. But that would’ve probably been a whole bunch of them, and I’m sorry, at least three or four guys managing to keep their mouths shut and keep their stories straight and not slip up even once? I don’t think so.’ Holly’s eyes went to Conway. She said, ‘Not if you questioned them the way you questioned us.’

I lifted the photo. Said, ‘Someone managed to keep her mouth shut this long.’

That spark of irritation again. ‘Everyone thinks girls blab everything, yap yap yap, like idiots. That’s total crap. Girls keep secrets. Guys are the ones who can’t keep their mouths shut.’

‘There’s a lot of girls blabbing on the Secret Place.’

‘Yeah, and if it wasn’t there, they wouldn’t blab. That’s what it’s for: to get us spilling our guts.’ A glance at Houlihan. Sweetly: ‘I’m sure it’s very valuable in lots of ways.’

I said, ‘Pick one thing to tell me about Chris. Something important.’

I saw the breath lift Holly’s chest, like she was bracing herself. She said, clear and cool, ‘He was a prick.’

Protest noise from Houlihan. No one cared.