Danny broke into the closed-circuit system of the newsagent on the corner and they all watched as Rose, Fiona and Gus were bundled into a grey van. Julie and Ian – who had given up flapping around and was now sitting on the floor beside them, his own laptop open – started tracking its progress through the road and traffic cameras all over the country. Suzy spoke to the Metropolitan Police to enlist their support and kept an open line between their ops room and SIS headquarters in Vauxhall.

They called out its progress. ‘Wood Green,’ Julie said.

‘Enfield,’ Ian added. ‘Now Harlow.’

‘Stevenage,’ Julie called back. ‘Where the hell are they going?’

‘Luton,’ Ian answered. ‘They’re in Luton.’

Kate had her eyes fixed on Danny’s laptop. He’d closed in on the men marching her children to the van in the dawn light. One had a snake tattooed on the back of his right hand.

So Danny was now working through all the databases at his disposal, from those at SIS to those kept by the Met, MI5 and the National Crime Agency. Only in the last did he get a match, and the file it connected them to made Kate want to throw up.

Arlind Sadiku, the man with the snake tattoo, was an Albanian gangster renowned for his control of the London cocaine trade and a penchant for extreme violence.

The last road camera the van had passed was on the way into Luton. The process of tracking it beyond that grew more complicated as Danny was forced to hop from one private CCTV system to another. Julie, Ian and Suzy joined him in the work and they eventually located the van in a car park outside a nondescript warehouse.

By now, the entire machinery and power of the British state were hurtling towards this small group of Albanian thugs. Sir Alan had been as good as his word and they were told that a team from Hereford was on standby.

Ian, who had picked up the role of point man inside the plane, wanted to know that he had Kate’s authorization for the SAS to go in. She nodded. What choice did they have?

They waited. Ian and Danny tracked the progress of the rescue through the SIS ops room, which was taking a video feed from SAS headquarters in Hereford. ‘Helicopters airborne,’ Ian said.

‘Three minutes,’ Danny said.

And then they counted down. Two. One. Thirty seconds. Twenty. Ten.

‘Roping down,’ Ian said.

‘Blowing doors,’ Danny added, a few seconds later.

‘Dogs in.’

There was silence. How long did it last? Ten seconds, twenty, a minute?

It felt as if it would never end.

And then, from Ian: ‘No one there. Damn. They’ve flown. They’ve gone. Jesus. How did they get away?’

There was no time for recriminations or doubt. They returned to leapfrogging the CCTV systems. Somewhere, somehow, they’d missed something.