‘It’s unusual, but it does happen occasionally if the rest of the evidence is strong enough. There used to be something called the “no body, no murder” rule. But things have changed since then, and you do see a few cases where the police proceed without a body, and still get a conviction.’

‘Like the Blaisdale case. The email from Ben.’

‘That would be one example, yes.’

‘What did Naylor say about the Facebook posts?’ I said, unable to keep the exasperation out of my voice. ‘The David Bramley account? Can’t he see that’s proof Ben’s still alive, for fuck’s sake?’

Larssen shrugged, unmoved by my frustration.

‘There’s no proof that Ben sent them. Anyone could have sent them. So their evidential value is limited.’

‘Can’t they trace the IP address they were sent from, trace the account in some way?’

‘Usually they can, if the person is using an existing mobile account, or a desktop PC, or accessing Facebook via the app on their phone – which is the way most people do it. That will leave a trace that they can pick up. But according to DS Redford, the Bramley Facebook posts and the Messenger texts you received were sent by someone using a pay-as-you-go phone, via a web browser rather than the app.’

‘And what does that mean?’

‘It means there is no trace. You’ve got multiple layers of disguise: not only is the Facebook account an empty shell, but you’re also not generating metadata via the app. And in any case, you’ve got nothing to link the IP address to apart from a pay-as-you-go phone, which apparently hasn’t been used for any other calls or texts, and hasn’t been topped up using a credit or debit card. It’s one of the few ways of evading this type of check. It basically gives the police a bit of a dead end.’

I shook my head.

‘Who the hell knows this stuff?’

‘Someone who’s very smart indeed. Someone who lives and breathes technology, and knows exactly what they’re doing.’

‘He lives and breathes it all right: Ben’s very much alive. You see that, don’t you?’

Larssen capped the end of his pen and put it down on the pad. He sat back in his chair.

‘You realise, Joe, that if they had found a body, they would have charged you already? Naylor certainly wouldn’t be so keen to lay out all of his new evidence.’

‘So why did he?’

‘Because he wants you to be overwhelmed by it all and admit that you did it. In the absence of a body, he’s looking for the next best thing: a confession.’

‘Well they’re not getting that from me, so what’s our plan of attack?’

‘Attack?’

‘What do we do next?’