Thierry executed a series of workarounds on the keyboard, and the computer transformed from a filmmaker’s laptop to a cell phone spinner, which used graphic boxes. Having locked on to an IMSI number, the number would be allocated to the box and other data such as time and connections would be filled in. Spinning machines did not operate the way they were portrayed in the movies—it was almost impossible to simply pick up someone’s cell phone and ‘track’ them with coordinates. The spinner—in reality, an IMSI catcher—just acted as a telecom tower connection on the local network. So what the mission team would see on the spinning laptop were the IMSI numbers from nearby phones connecting to the ‘tower’ that sat inside this laptop. If there were a lot of people with phones around, there’d be a lot of numbers. If a phone was not moving, the number would remain on the screen, but other numbers would come and go, meaning those phones were moving in relation to the laptop. After a few days, the team would have a group of numbers which could be of interest and which would be registered in the system. That’s when the team would follow the car of interest, and because the mission team’s car would be following at the same speed, only the phones located in that car would stay connected to the laptop. Those numbers would switch from one antenna to another along the travel route, but the phones would always be connected to the spinning laptop, as if the laptop were a permanently available cellular tower.

Brent continued. ‘We use the antennas around the screen to line up our target, and when we lock on we harvest the IMSI and the IMEI numbers.’

While IMSI was stored on a SIM card, the IMEI was the international mobile equipment identity—the identity number given to each phone, behind the battery. Most networks also stored the IMEI in an equipment identity register which contained all legitimate cell phone IMEIs, allowing the cell network owners to identify stolen or non-complying phones.

‘Excellent,’ said de Payns. ‘Briffaut wants us in-country by next Sunday, which gives us a whole working week to do our thing. Everyone okay with that?’

‘We’re good,’ said Brent.

CHAPTER NINETEEN

CHAPTER

NINETEEN

He put the battery into his phone as he reached street level at the Metro and when it powered up there were two text messages from Romy. Both asked him to call her. He made the call as he walked with the late afternoon commuters.

‘Hi, honey, how are you?’ he asked as she picked up. His hangover was still substantial.

‘Just wanted to check with you,’ she said. ‘Ana invited us to dinner.’

De Payns dodged other walkers, also with phones to their ears.

‘Um …’

‘The kids are very close,’ said Romy. ‘They pushed for this.’