We’d been taught that if a hostile party is watching for an officer to make a brush pass they’ll check the people in your vicinity. But surveillance teams rarely think – or have the means – to look vertically. And in a shopping centre, twenty-metre radius in all directions can give you a hundred people to profile.

There were a lot of candidates, but after half an hour I had a favourite.

Directly above the KFC, on the upper-level food court, was a Dunkin’ Donuts. At one minute past midday a man walked in. He was in his twenties and jumpy. He wore an identical blue puffa jacket to the corpse I’d seen last night.

He bought food and a drink, sat down, set up his laptop. Grey, brimmed cap pulled low, scarf up. As close as you could get to obscuring your face without becoming conspicuous.

The timing synced closely with Joanna’s. They left within a few minutes of each other. He got to his feet, looked around, moved off fast. The tray remained on his table, food untouched.

I watched three more times and then I was sure. Her man delivered information. He’d got something. He was a source that required extreme caution, one that she’d decided not to disclose to her employer.

Plenty of potential reasons for reticence. Certainly in Six, where potential agents required a complete risk-profile and managerial clearance before you could engage them, it was worth sidestepping bureaucracy at first. And then, even buried under codenames, they were on the system, and systems leaked.

Who was he?

No news of any individuals reported missing.

I speculated a timeline: the next day they meet at the rented apartment. He’s packed quickly, ready to leave. Something’s gone wrong. They’ve been discovered. She tries to call me before leaving. Perhaps they know their phones are compromised.

But only she got away.

She fled, injured, sent me the video file then ran. Where would she run?

I drove out, towards the block I’d visited last night. As I was approaching I saw police parked outside. A full forensics team was active. I kept driving in the direction of the internet café. She’d been heading due north. I stopped and checked a map. I was heading beyond the edge of the city. There was an hour or so of daylight left and I thought I’d make use of it.

Time spooled backwards as you left Astana, shiny buildings becoming construction sites, bare frames, then grey foundations, then rubble. I passed a police car sitting in the shelter of a billboard with the President’s face and the words: Project Astana 2050. Then you reached the desert.