O’Kelly turns around. He leans back against the window and examines us. His shave went wrong this morning; his face is raw and flaky, like he’s slowly eroding away. ‘D’you know what ye’re acting like?’ he asks.

We wait.

‘Ye’re acting like you don’t have a suspect. Flailing about, haring off in every direction after anything you see. That’s how Ds act who’ve got nothing.’ His eyes move from Steve to me. ‘But you’ve got a perfectly good suspect right in front of you. So what am I missing? What’s wrong with Rory Fallon?’

I say, ‘Everything we’ve got on Fallon is circumstantial. We’ve got nothing solid tying him to the actual killing: no blood on his gear, none of his blood or hair on the victim, no injuries to his knuckles. We can’t even put him inside her house. We’ve got no motive. We’re still working on all of that, and if the Bureau comes back to me saying they found fibres from Aislinn’s carpet all over Rory’s trousers, then yeah, I’ll be paying a lot less attention to other possibilities. But as long as it’s all circumstantial, I’m gonna keep chasing down other scenarios and ruling them out. I don’t want to get Fallon into court and have the defence whip out a witness who saw Aislinn having a massive fight with some guy who looks nothing like him.’

O’Kelly’s pulled a handful of stuff out of his pocket – paper clip, twisted tissue, a pebble – and he’s turning through it slowly, not looking at me. He asks, ‘Why didn’t you have him back in today?’

And it’s been a long time since any gaffer made me explain my decisions, in a case that wasn’t going off the rails or anywhere near it. If I was positive this was just O’Kelly giving me shite to try and nudge me out the door, I’d be raging; but I’m nothing like positive. I think of Breslin’s roll of fifties, and of O’Kelly at the roster saying Breslin’s due in. Have him. The air of the building feels like it’s changing into something different, something gathering speed and ready to switchback any second; something I know I should have more cop-on than to love.

I say, just bolshie enough, ‘Because I didn’t want to. When we get everything back from the Bureau, then we’ll haul him in and hit him hard. He’s the nervy type; letting him stew for a couple of days won’t do any harm.’

O’Kelly’s eyes hit my face for a second, needle-sharp, and then flick away again. He pulls a battered throat lozenge out of the pile in his hand and examines it with faint disgust. ‘I don’t know what you’re so happy about, Conway.’