‘Our working theory,’ I say, ‘is that Fallon arrived at the vic’s place around half-seven, things went bad somehow, and he punched her. We’re guessing he thought she was just knocked out; he legged it home and hoped she wouldn’t call the cops on him, or wouldn’t remember what happened.’

That has Breslin nodding along approvingly, giving the newbies’ little theory his blessing. ‘More like manslaughter than murder,’ he says, ‘but that’s not our problem.’

‘By early this morning,’ I say, ‘either Fallon’s conscience got to him, or else he’d talked to a mate who wanted to do the right thing. An anonymous male caller reported to Stoneybatter station that there was a woman with head injuries at 26 Viking Gardens, and requested an ambulance.’

‘My money’s on Fallon doing it himself,’ Breslin says. ‘He’s exactly the type who’d bottle it after a few hours, start trying to put things right just when it’s too late.’

‘The phone number came up private,’ Steve says. ‘Who wants to get on it?’

All their hands shoot up. ‘Easy there, boys,’ Breslin says, grinning. ‘There’s plenty to go round.’

‘Gaffney, you take the phone number,’ I say – I need to give the kid a pat, settle him after the mug thing. Meehan writes that down. ‘Stanton, Deasy: you were working on a list of Fallon’s KAs. How’s that going?’

‘Nothing surprising,’ Stanton says. ‘Mother, father, two older brothers, no sisters; handful of mates from school and college, a few ex-flatmates, long list of work colleagues and friends – mostly history teachers, librarians, that kind of thing. I’ll e-mail it on to you.’

‘Do that. Detective Breslin, you’ve already started talking to the KAs, am I right?’

‘Both Fallon’s brothers sounded appropriately shocked,’ Breslin says. ‘According to them, they knew about Rory’s big date, but that’s as far as they’d got; they were waiting to hear all the dirty details. They claim they didn’t ring Stoneybatter station this morning, or ever, but then they would, wouldn’t they? I’ve got them both coming in for separate chats after this.’

Breslin’s planning on working a long shift, for a bog-standard case. ‘If they don’t pan out, keep working your way down the list,’ I say. ‘Start with anyone who lives near Rory’s route home, where he could’ve got a surprise visit last night. And while you’re at it, get the brothers and the best mates on tape. We need to run their voices and Fallon’s past the guy at Stoneybatter who took the call, see if he recognises any of them. Can you follow that up?’