The room’s the same as last time – same soft chairs, same biscuits on the table, same picture on the wall – but the woman with Rose is different, a quietly smiling woman from Social Services whose name Evan can’t recall.

‘Thanks for coming back, Evan,’ says Rose. ‘Sit down wherever you like. Have you been OK since we talked?’

Evan nods. Rose thinks he looks a little pale, as if he might not have slept well.

‘All we want to ask you to do today is have a look at some photographs.’

Evan stiffens, and Rose knows he’s thinking of the offender portfolio, a nightmare gallery of men who’d trouble anyone’s dreams.

‘They’re pictures of bridges today, Evan. We’ve tried to narrow down the town where you might have been held. With the description you gave us, we’ve come up with some possibilities. Even if you can’t tell us for sure that we’re on the right track, if you can say that some definitely aren’t the place, that’s a help in itself. What I’m saying is, a no is as useful as a yes. So will you have a look?’

Evan nods again. He’s retreated into silence, and that troubles her, since it’s likely to be their interview that’s set him back. At the same time, she’s a realist, and knows that can’t be helped. Getting to Liam Keslake is the number one driver now.

They’ve all done their best to find high-quality photos from every possible angle. She agreed to take Manchester, and since they’re the ones she’s most familiar with, she decides to show them first.

She lays out six pictures of bridges, some over the canal, some over the river. Evan seems willing to co-operate and leans forward to get a good look, but she can see from his expression there’s no recognition there.

He shakes his head.

Next, the Tyne Bridge in Newcastle with the High Level Bridge behind. There’s actually a third bridge in between them, but from many angles you wouldn’t know. There are four photos of these bridges, and Evan studies them for a while.

‘Might it be these, Evan?’ asks Rose.

‘I don’t know,’ says Evan. ‘Maybe. I’m not sure.’

‘We’ll leave this town in as a possibility, then.’

She moves on to Glasgow, but he rejects the pictures out of hand.

‘That’s not it. The river didn’t look like that.’

Knowing Campbell will be pleased to have both Manchester and Glasgow in the reject pile, Rose moves on.

Sunderland. Again, he considers for a while.

‘Maybe.’

‘OK. This place?’

She shows him pictures of Rochester. She has to admit, she’s finding this tricky herself. One bridge looks very much like another after a while, and the rivers they cross look almost identical.

He shakes his head.

‘I don’t know.’