Joanne pouted. ‘We helped you. Now that you’ve got what you want off us, you’re just going to dump us and run?’

‘Typical guy,’ said Gemma, up to the branches, shaking her head.

Joanne said, ‘I told you before. I don’t let guys treat me like crap.’

Some first warning got to me, through the Go go go drumming in my ears. I said, ‘I’m under a bit of time pressure, is all. It’s not that I don’t appreciate what you’ve done for me. Believe me.’

Joanne said, ‘Then stay.’ Lifted one finger and laid it on my knee. Cute nose-wrinkle smile, like a joke, but half a second too late. Orla sucked in breath, shocked, and giggled it out.

Somehow I stopped myself from leaping and running. If I fucked up now, I was fucked a dozen ways.

Gemma said, ‘Don’t look so terrified. We’re fun. Honest.’

Smiling at me, her too. It looked friendly, but she was written in a code I couldn’t begin to read. They all were. That bad-alleyway prickle that had faded for a bit, while they had me busy feeling like something they wanted and loving it; that was rising hard up the back of my neck again.

Joanne’s fingernail ran an inch higher up my thigh. All of them giggling, tongues nipped between sharp little teeth. It was a game, and I was part of it, but I couldn’t tell what part. I tried laughing. They laughed back.

‘So,’ Joanne said. Another inch. ‘Talk to us.’

Smack her hand away, leg it back to the school like my arse was on fire, bang on the art-room door and beg Conway to let me back in if I promised to be good. Instead I said, ‘Let’s think this through for a second. Shall we?’

Put on my stuffiest voice. Thought teacher, thought McKenna, thought everything they didn’t want. Picked them out one by one, looking them in the eye, separating them out: not triple and dangerous; just schoolgirls being very silly.

‘Gemma, I realise that it took a lot of courage for you to give me this information. And Joanne, I realise that Gemma probably wouldn’t have plucked up that courage without your support – and yours, Orla. So, after you’ve gone to considerable trouble to bring me this potentially valuable material, I’m not inclined to waste it.’

They were looking at me like I’d gone flash-bang and turned two-headed. Joanne’s finger had stopped moving.