Tuesday morning, and everyone’s in so early, by 8 a.m., the coffee machine is on its second refill. Naylor’s trying to make good use of her time, going through some of the statements on a new incident where a businessman and his family were robbed at gunpoint. It’s a serious case – shotguns, violence and three traumatised children – and it should be getting her full attention, but her mind’s on what she hopes is happening in Sunderland.

A few minutes after nine, Campbell walks into the office, sharp-suited and overloaded with aftershave. For once, he doesn’t have to call for attention. All eyes are on him, and a hush falls on the room.

‘OK, listen up,’ he says, unnecessarily. ‘I’ve just got off the phone with Northumbria, and I’m pleased to report a fantastic result from there.’

Naylor’s surprised to notice she has butterflies in her stomach, and finds herself willing Campbell to say what she wants to hear.

Campbell glances at his page of notes.

‘Acting on information received from Gareth – known as Gary – Prentice, forced entry was made at an address in Sunderland early this morning. Two children – two children, ladies and gentlemen – were removed from the scene, one female, aged approximately six years old, identity not yet established – an interpreter is being sought – and one male aged eleven, who gave his name as Liam Keslake.’

A cheer goes up around the office. Naylor turns to Hagen, who’s grinning, and Hagen gives her a double thumbs up. From across the room, a smiling Dallabrida gives her a wink.

‘Furthermore,’ goes on Campbell, when they settle back down, ‘two arrests were made at the location and a further two have subsequently been made at addresses in Lancashire and Essex. Four men remain in custody to be charged with a range of offences. They are . . .’ He looks again at his notes. ‘Brian William Birch, Daniel Kawcznski, Neil Alexander Roper and Peter Clive Sewell. I’ve been asked to pass on thanks from both Northumbria and the Chief Constable to everyone who’s played a part in what I think we can call a highly successful operation, which will of course be front and centre in the press when the news breaks. So, well done everyone. Great result.’

When Campbell’s gone, the air of celebration remains, but as Naylor approaches Hagen, her delight at Liam being found is tainted by the feeling that the path they followed to make the arrests was too long and too slow.

She sees the same in Hagen’s face.

‘Is it a great result?’ she asks.

Hagen shrugs.

‘We did our best,’ he says. ‘And they got Liam out.’

‘We might have got to Brian Birch earlier, if Border Control had been able to confirm in a timely manner he never went to Spain. That was a clever plan, shipping his missus over there as a decoy.’