Tom woke at seven, dressed quickly, and crept out of the hotel room, leaving Pet sleeping peacefully, her face almost child-like as she dozed.

He walked to the local shops and bought toothbrushes and toothpaste for them both. He also picked up two large coffees and muffins from the nearby coffee shop.

Key-carding his way back into the room, he found Pet dressed in a hotel towelling robe, her hair damp from the shower. She was sat in front of her laptop with an intense look of concentration on her face.

‘I’m just accessing the phone databases. I’ve searched for the 219 number that sent all the damning texts to your friend Martin Green, aka Bojan Dedic. Thanks,’ she said with a smile as Tom handed her a coffee and a muffin.

‘And?’

‘219 is an unregistered pre-pay, no top-up data. Nothing, nada, nix,’ she said, sipping on the coffee. She broke off a piece of the muffin and put it in her mouth.

‘I’ve got in-and-out call data with cell sites which shows limited use only, most of which we know about from Dedic’s phone. But the cell sites put it close to the City Road address you said the Brankos lived at, so I imagine that’s their base of operations.’

‘There is one other number it calls and is called by: one ending 079. That’s also a burner phone with nothing known about it. But that number made the call to 219 just before your photo got sent to Dedic by 219. That number has been hitting cell sites in SW1 when it calls into 219.’ She was obviously proud of the speed of her work.

Tom thought it through. 219 received a call from someone at Scotland Yard about the warrant card. 219 then sent Dedic to get the warrant card. He then sent a photograph of Tom with his personal details after 219 received a call from the new number in London SW1, presumably despatching Dedic to intercept Tom.

‘Bring me up a map of the cell site in SW1.’

Pet’s fingers sped across the keyboard and brought up Google Maps, with an arrow pointing at a street in Central London.

Tom stared at the screen, a knot forming in his stomach.

‘That’s a National Crime Agency office. They run intercepts from there. Jesus, they’ve had my phone hooked up.’

The realisation of the true scale of the resources being deployed against him struck home. Intercepts were only used in terrorism cases and the most serious of life-threatening crimes. They needed enormous resources to apply for and obtain the warrant, which then had to be signed by the Home Secretary.

Just who was leading all this? Tom’s mind raced.

‘I need to hear what the Brankos are talking about. Can you sort an intercept?’

‘No. No chance. I just can’t get access to that; we don’t even have a back-door route,’ she said apologetically. ‘You could bug their house easily enough.’