‘Those blocks of flats, though,’ says Rose. ‘They’re low-rise rather than high-rise. I got the impression from Evan he was on a really high floor.’

‘He didn’t really know, though, did he?’ Hagen puts in. ‘I say this one’s a possibility.’

‘I agree,’ says Campbell. ‘How many of these possibles are there, Bradley?’

Hagen glances at his notes.

‘Seven in total, Sir. But I think good possibilities, maybe three or four.’

‘Carry on, then,’ Campbell says.

There’s a lengthy discussion on Manchester, where two or even three sites look like possibilities.

‘Plus it’s not far from where Liam was taken,’ Hagen says.

‘That’s a daunting prospect,’ says Rose. ‘Just look at all those flats.’

‘Doesn’t that make it all the more probable?’ asks Naylor. ‘Sadly for us.’

‘It’s in,’ says Campbell. ‘We’ll make use of Greater Manchester intelligence. Next.’

A new picture appears on the screen.

‘Sunderland,’ Hagen says. ‘Same set-up as Rochester, a road and a rail bridge running parallel. And plenty of high-rises to go at.’

‘Yep,’ says Campbell. ‘Next.’

‘Newcastle,’ says Hagen. ‘Same again. The good news is with this one, the bridge has that distinctive green arch, which Evan’s likely to remember.’

‘Got it,’ says Campbell. ‘Next.’

‘This is the last one,’ says Hagen. ‘Glasgow. I’ve put this one in as an aerial view, because to my mind it’s like London. There may be too many bridges. If you could see bridges, chances are you’d see more than two.’

Naylor looks sceptical.

‘I’m not sure. If you were in those flats down the bottom there, you might only see one, but from those on the far bank, you’d see . . . It’s impossible to say without going there and taking in the view. I think it has to be in.’

‘So where does that leave us?’ Rose asks.

‘We’ve got five possibles,’ Hagen says. ‘Glasgow, Manchester, Sunderland, Newcastle and Rochester.’

‘I love the way you say Newcastle,’ Rose smiles. ‘Newcastle.’

‘There has to be a plan,’ Hagen says. ‘We don’t have the resources to go charging off to all points of the compass on the off-chance we’ll find the right room with the right view.’

‘Too right,’ says Campbell.

‘We have to narrow it down,’ Naylor says. ‘I think the only way to proceed is to print off a montage of all of these places from as many angles as we can find and run them by Evan. Even if he only rules a couple out, it’ll be something.’

‘Just pray he rules out Manchester and Glasgow,’ says Hagen, ‘though I have a horrible feeling those are the ones that he’ll leave in.’

‘God help us then,’ says Campbell.