While Pet tapped away, Tom dug out the SD card and picked up a blank envelope from the rosewood desk in the corner of the room. Tucking the SD card inside, he scribbled his old friend Buster’s address on the front of the envelope. Buster was now also a cop; he’d joined the year after Tom and was serving as a Detective Constable in the Met’s Professional Standards branch, where he’d joined straight from the City of London Force as a ‘clean skin’ officer, working in anti-corruption. There had been suspicions of organised corruption in a few squads, and the Met had imported some new blood from outside forces to root out the problem.

Tom needed the SD card away from him, and a couple of days in the postal system and then in the care of his old friend would keep it as safe as could be reasonably expected. There was no link between Tom and Buster on record, despite them serving together in the SRR. The discharge papers said that Tom left the Royal Marines and Buster left the Parachute Regiment, which was a side-benefit of SRR not officially existing as far as the public were concerned. He scribbled a brief note on a Post-It note: ‘Buster, guard this with your life and I’ll be in touch soon. Keep it firmly under your hat. Love, Borat.’

Signing off with his old nickname, known only to Buster, was an instinctive safety measure to keep their association quiet.

‘Okay, looks like Ana is still in the UK. The phone has been busy with lots of calls in and out and messages hitting cell sites in Islington, close to Upper Street. Looking at the traffic on the escort site, she is still working.’

Tom went into his phone’s contact list and read out the numbers he had for Mira, Aleks and Luka.

‘Any trace of those numbers on her call history?’

‘Mira’s number was calling it until three days ago, but no trace of the other two.’

So it would seem she wasn’t working for the Brankos any longer. That wasn’t unusual; working girls often changed hands between pimps for a fee.

It still didn’t answer the question of whether it was safe to call Ana. She may have new pimps who wouldn’t like it, and they might go straight to the Brankos. He couldn’t pose as a client as that could just be walking straight into their hands if the Brankos were still controlling her. The other factor weighing heavily on Tom’s mind was that he didn’t want to expose Ana to risk; they’d kill her just as quickly as they killed Ivan.