‘All of that leaves us with some good lines of inquiry and a mountain of work. Priorities are as follows. One – find out where Abu Mujahid went in this missing ninety-five minutes in West London. Two – identify the four young men. And three – we scour the Lake District for signs of Abu Mujahid, whether he’s there now, or whether he’s back in London. It seems hard to believe that a cell is launching a major terror attack in the Lake District in the middle of winter, unless they’re really pissed off about sheep. Are they training? Are they plotting? We are working closely with North West CTU on this and they are taking the lead here.

‘And in addition to all of that, we will continue to chase down the international links, and work with Thames on looking for phones for these guys. Listen. It’s taken some time, but we are finally on his tail. We now know where Abu Mujahid was four days ago – and I’m confident by the end of the day, we’ll have pinned him down further, that we’ll know the identity of those four men. Each hour we catch up with him means we are an hour closer to stopping whatever he is planning.’

#

Three hours later, Bose was at Gabriel’s desk.

‘We’ve got a breakthrough on Abu Mujahid’s associates,’ she said, breathing a little too hard.

‘Explain?’

‘We had the CCTV of the four young men with Abu Mujahid at the service station. We put it through facial recognition overnight, but nothing’s come up.’

That didn’t surprise Gabriel. Despite the hype, facial recognition software was largely hopeless. It worked well enough if pictures were lit and the face was staring at the camera. But with screen grabs from grainy CCTV, it failed to deliver more often than it worked.

Bose continued: ‘This morning we’ve had the team looking through CCTV footage of Abu Mujahid and his van six days ago, driving around North London. Pretty quickly, it’s become apparent he was picking up his group, mostly from Islington and Hackney. We’ve found CCTV of two pickups – both in public areas. Two men got in the van around 9am, a third ten minutes later. We’ve not found the fourth pickup yet, but it won’t be long.

‘The next job was to ID the four men. And that’s when the penny dropped. Because I think we know one already. Two days ago, the University of Islington got a call from the parents of an engineering student – second year, Islamist supporter, from Cardiff. The family are third-generation Somali, all very respectable, and worried that their son – Omar Asad – had vanished off the face of the earth. Asad was on the university radar because he was hanging around with some potential unsavouries – but there was insufficient evidence for an intervention under Prevent. This time the university passed it on and it’s been sitting on my computer for forty-eight hours along with a picture of Asad. It’s the same man from the motorway service-station CCTV.’