‘What do you mean?’ Could he be talking about providing details of his whereabouts on the dates of Billy’s murders? That, as Sam had explained on the phone, was the purpose of this meeting.

‘What do you think I mean?’ Kearns laughed. ‘I’m not letting this fucker Billy Dead Mates make a dog’s breakfast of my love life. The intel I’ve had so far suggests he might want to kill my wife. If she’s dead she can’t take me back, whereas if she lives I’m going to make sure she does, you see. So how are we going to stop him from killing her and instead usher him into a claustrophobic jail cell? Note: I say “we”, not “you”. I’m at your disposal, Sergeant.’

‘Um …’

Sam was still formulating his reply to the surprising onslaught when Kearns launched a new verbal assault. ‘Of course, Kim’s in danger twice over, as I see it. Not only from Billy, but also from you guys.’

‘I’m not sure what you mean,’ Sam said truthfully.

‘One of the murder victims was Malevolent Marion. I know it’s not public knowledge yet. Kim told me. See, I’m still the one she turns to in times of trouble. She won’t be willing to pretend she didn’t have a low opinion of the old bag, so you’re bound to suspect her.’

‘Suspect Kim? Of killing Marion?’ Sam wanted to be sure.

‘Yes.’

‘Why would she want to kill the others, though – Billy’s first four victims?’

‘She wouldn’t. Kim would never kill anyone. I would, without hesitation. Don’t worry, I’m not Billy. I have alibis for every one of the five: full house.’ Kearns beamed at Sam. ‘I was at work while Billy was doing his stuff – my colleagues at De Bonis will vouch.’

Sam believed him, and half wished he didn’t. There was something of the pantomime villain about Gabriel Kearns; he was a man one might enjoy hating.

‘I’ve never bought into any of that self-serving sanctity-of-human-life claptrap that people like to put about,’ Kearns said. ‘Have you?’

‘I have, yes.’

‘Oh. Well, I suppose you’d have to, to do your job. Back to Kim … I hope you heard my point: killing’s not in her repertoire and never could be. She’s too contrary.’

‘What do you mean?’