‘No idea,’ Jake says, surprised. Odd that they didn’t mention it when they took his statement. ‘I was with them both last night. On the canal. They came out to investigate the fire.’

‘Maybe that’s why they’re down here. I didn’t have time to find out before they asked me to leave.’

‘They don’t think it was Kate?’

‘Of course they bloody don’t. Kate? She loved that boat.’

‘Did she? I think she hated it by the end.’

They must be going to talk to her about the CCTV footage, see if she remembers anything about that night. She won’t like a visit from the police. Doesn’t want anything to do with her past life. With him.

‘Is everything OK? With Kate?’ he asks. ‘You sound—’

‘Everything’s fine.’

She pauses. He knows something’s wrong. It might explain why she’s being so nice to him all of a sudden. And he’s happy to wait, resist filling the silence until she tells him.

‘Did she ever talk to you about doubles?’ Bex asks eventually.

‘Doubles? Not that I remember. Except when I was ordering too many at the bar.’

Jake has a weakness for Talisker, an expensive habit that didn’t help their finances.

‘I’m serious, Jake. She’s become fixated with the whole idea down here. Thinks that Rob might be…’

‘Might be what?’ Jake has no idea where Bex is going with this.

‘She thinks Rob might have been replaced by a doppelgänger,’ Bex continues. ‘Apparently he spoke to her about it once, said he has this fear of meeting his double, that the double would take over his life. And what’s really freaking her out, she says, is that he did actually meet someone who looked just like him, when he was younger, on a beach in Thailand. It’s meant to be bad luck if you meet your doppelgänger once. Meet them twice and you’re toast. She’s been unable to get the idea out of her head ever since.’

‘That doesn’t sound like Kate,’ Jake says.

‘I know. And last night she saw this footage on French TV, an interview with Rob about his new tech office in Brittany or something. She woke me at one thirty in the morning to watch it, convinced that it wasn’t Rob. It was all very weird. Apparently Rob doesn’t speak a word of French – Kate’s been trying to teach him – but this guy was talking fluently. And then we found a French book in Rob’s office. I told her he’s just a quick learner but she’s really worried by it, thinks she’s going mad.’

Jake pauses for a moment, trying to take in what Bex has just said about Kate. ‘Ever see Invasion of the Body Snatchers?’ he asks. ‘Nineteen fifties sci-fi horror movie about alien clones?’