Breslin shrugs. ‘I suppose you might be able to argue that. Like I said, it’s a cute story. But that’s all it is. There’s nothing solid underneath. You can prove that Mac had an affair with Aislinn. Good for you. But when it comes to Saturday night, you can prove exactly bugger-all. You’ve got an ID from the prime suspect, who has every motive to drag someone else into this mess. You’ve got some bizarre convoluted story you heard from some woman who may or may not have been the vic’s best friend, may or may not have been in love with the vic herself, and may or may not be holding a jealous grudge against the lucky guy who got to shag the vic. And if you actually get a warrant to search Mac’s gaff, which I can’t believe you’d be stupid enough to do, you’ll probably have proof that he’s lost his brown gloves. And that’s it. That’s what you’ve got.’

Silence.

‘What are you planning to do with it?’

More silence.

‘Yeah. That’s what I thought.’ Breslin fills himself another cup of water, and we listen to the bubbles force their way up the cooler. He takes a long deliberate sip before he says, ‘I hope you two realise what you’ve done to this case.’

Neither of us bites.

‘You’ve fucked it right up the ass. Do you get that? You’ll never get McCann for this, because A, you’ve got no evidence that he did it, and B, he didn’t do it, Fallon did. If you actually try going after Mac, the prosecutor will laugh your file right out of his office. If you somehow manage to get him into court – which you won’t – the defence will pull in Rory Fallon and your mountain of actual evidence against him, and the jury will acquit before the jury-room door closes. Wouldn’t you? Be honest. If you were on the jury, and the sum total of the evidence was what you’ve just told me, would you vote to convict?’

Me and Steve don’t answer.

‘Of course you wouldn’t. Neither would anyone else in the country, except maybe the odd cop-hater who’d vote to convict him of being Jack the Ripper. But now that you’ve opened up this whole can of worms with Mac, you’re never going to get Fallon. The prosecutors get him into court, the defence pulls in McCann – wrecks his marriage and possibly his career in the process, but hey, that’s not your problem, am I right? – and bang, reasonable doubt. Bye-bye, Rory. Have a nice life. See you when your next girlfriend pisses you off.’

He raises his cup to an imaginary Rory.