‘Arm’s length. But Vishinsky is close to Putin. Nothing’s going to happen without approval.’

‘And it dates back to Ukraine?’

‘It pre-dates Ukraine. It’s drawn from psychological work the Main Intelligence Directorate was doing in the Sixties. But we started getting a concrete picture of how it functions in 2014. I think Joanna was working on it before leaving Six. I need you to back me and redirect resources. I think she’s alive. She found out something about Russia and Kazakhstan.’

We were in the private room of a canteen inside the White and Chase building, away from other suits, a platter of sushi going to waste between us. Walker had collected me from reception, dropped some unspecified paperwork off in his temporary office, which gave me another view of the keypad and the electronics set-up. He’d been hungry so we went up to the canteen, which he’d assured me was secure. I’d decided not to mention my own arrest, or run-in with Sergei Cherenkov, partly to see if Walker knew. So far there was no suggestion he did.

‘Vishinsky represents an expansionist, hawkish, ultra-cynical circle at the heart of the Kremlin,’ I said. ‘They push a narrative that NATO is seeking to encircle Russia. When they wanted Crimea annexed, Vishinsky had to assure Putin it could work. He masterminded the combining of cyber warfare, kinetic attacks, propaganda and what the Russians call Maskirovka: masking, military deception. He was on the ground, coordinating it. Now he’s here.’

‘Why now?’

‘I don’t know. I think Joanna knows. She tried to get out. Look.’

I showed him the file Shomko had sent through. Walker studied the plane tickets to Caracas, the fake names. I wanted to see how he’d react. If this didn’t get his support he either knew where she was or he didn’t care.

‘How did you get this?’ he asked.

‘I bought it. The investigation concerning Joanna has been moved away from the units you’d expect to be handling a murder. This is from anti-terrorism. Chief of Kazakh anti-terrorism is Rakim Zhaparov.’

Walker nodded as if this made sense. He pincered some sashimi.

‘It fits the picture we’re building. There’s Kremlin ties.’

‘What do you know about him?’

Walker chewed, considering. ‘Relatively young, ambitious. Supposedly waging a war against militant Islam. Close to Moscow. Not a pleasant creature if certain reports are anything to go by. And he’s caused us problems before. He wants Saracen out of Kazakhstan. Wants all US and European companies out.’

‘Has he got the muscle to do that?’