‘You’re the boss,’ he says, with a sigh. He leaves the photos and tilts his chair back, listening.

‘OK,’ I say. ‘Aislinn had the cooker on, right? Making Rory that lovely fancy dinner.’

‘Yeah. And?’

‘And before Rory left, he turned it off.’

Rory starts to say, ‘I wasn’t—’ but Breslin lifts a hand to shut him up. ‘Right. That’s important how?’

‘The only reason to turn it off,’ I say, ‘would be that he didn’t want the house going on fire. Now, if Rory knew Aislinn was dead, or if he didn’t care whether she died or not – hang on a sec’ – Rory’s trying to talk again – ‘then his best bet would be to let the place burn. The house goes up in smoke, so does any evidence that he was there: the fibres, the prints, the DNA, the lot. Anyone who’s ever seen a cop show on the telly would know that. Amn’t I right?’

‘I’m listening,’ says Breslin. To Rory, who’s practically coming out of his seat: ‘You might want to sit down and pay attention to this, pal. It sounds like it might actually do you some good, and just being straight with you, you can’t afford to miss anything that’ll do that.’

After a second Rory sits back. His chest is going up and down like he’s been running.

Breslin asks, ‘Are you going to let Detective Conway finish what she’s saying?’

‘Yes. I will.’ When Breslin’s raised eyebrow prompts him: ‘Sorry. For interrupting.’

‘My point is,’ I say, ‘the only reason Rory wouldn’t want the place going on fire would be if he didn’t think Aislinn was dead, and he didn’t want her to die. Meaning he never intended to kill her.’

‘Ah-ha,’ Breslin says, nodding slowly. ‘Now I see what you’re getting at, Detective. You’re right: it is important. Everything else we’ve got looks like murder, and a pretty nasty one too; but if you’re right about why that cooker got turned off, then it’s not murder at all. It’s manslaughter.’

‘Exactly,’ I say. ‘If I’m right.’

‘If. There’s any number of reasons that cooker could’ve been turned off. Maybe Aislinn turned it off herself. Or maybe Rory’s got a touch of OCD going on, can’t leave a house without turning all the appliances off. But if you’re right . . .’

We both look at Rory. He’s glazing over. Too many stories logjamming in his head: he’s starting to lose hold of them all. Up to a point, this works for us: if the guy can’t keep track of what he’s said about what when, he gets sloppy. Too far past that point, though, he just stops making sense. If we’re gonna get anything out of Rory, it needs to be soon.