More tapping of keys. ‘Okay, there was a call from this number this morning at 0700 hours lasting two minutes.’ She pointed at the number on a chart on the screen.

‘I recognise that number,’ said Tom, shocked. ‘That’s the Met switchboard number at Scotland Yard. Can we find out extension numbers or where it came from?’

‘Not from this phone. I’d need to hack into the systems and, even then, there’s no guarantee.’

Tom clenched his fists, ‘Okay. Carry on.’

‘A ninety second call was received from a cellphone number ending in 219 at 1105 hours. We can check these out once we’ve finished the download.’

Tom nodded as she continued.

‘Okay. Two SMS messages: one sent at 0820 hours from this handset to 219 saying, “Card obtained, I’m ready when you hear”. The next one was at 0835 hours which includes a photo of you, your name, date of birth and an address in Camden. See?’ She pointed at the laptop screen.

Tom was shocked to see his warrant card photo staring from the screen at him. It was also disconcerting to see his home address in the text. Jesus, how much influence did these people have?

It made some degree of sense. ‘Martin’ received a call from someone at Scotland Yard at 0700 hours, possibly arranging to get the warrant card. He then sent a message at 0820 hours, seemingly once he’d got the warrant card, saying he was ready to go, and received a reply at 0835 hours with photographs and details of Tom’s movements.

The crucial call was then made at 1105 hours after he received the call from Neil Wilkinson about the threat.

The key was the phone number: who had 219? That person was at the centre of everything, coordinating the activity against Tom.

He looked at Pet. ‘Can you get me phone call data for that mobile? I need in-and-out call and message data with cell sites.’

‘I reckon so, but it will cost you something to eat. I’m starving,’ Pet said with a grin.

‘In a minute,’ said Tom. ‘Can you overlay GPS data for the phone with the calls?’

Pet’s fingers flashed across the keyboard again, pausing only to brush her fringe to one side, a look of fierce concentration across her fine features.

‘Here,’ she said, pointing to the screen, where a map showed the route the phone’s GPS function had tracked since being switched on. The highlighted route first appeared close to City Road in Central London, adjacent to the flat shared by the Brankos. The first call at 0700 hours was received there almost as soon as the phone was switched on. The phone remained static for a while before going to Victoria Embankment and into New Scotland Yard. It remained static before sending the message saying the card had been obtained at 0820 hours.