We didn’t arrange to meet. I walked out, checked the parked cars, continued back to my hotel.

If Joanna had left Six, I thought, where would she go? Former spies move into banking or private intelligence. She was no more a City person than I was. I called around a few ex-colleagues now working private for the poachers: Stratfor, Kroll, Hakluyt. None had come across her on the scene.

Flax and Kerrigan’s had been open two days – a ‘soft opening’, which meant members of the public couldn’t get in but Olivia Gresham could. She was a portfolio manager who had set up her own fund around the time I started working in the Middle East. Like a lot of jobs, 95 per cent of espionage was contacts. Swapping thumb drives in underground car parks can be fun, but a remarkable amount involved simply belonging to a select group of people able to exchange information that others didn’t have. Like a journalist, you cultivated a network of off-the-record sources, only for a paper with the smallest distribution possible.

Investors were good. The exposure of several million pounds seemed to sharpen their appetite for knowledge. They, at least, knew where the wars were.

‘My favourite civil servant,’ Gresham said. ‘You look like you could do with a square meal. Go wild.’

Olivia Gresham passed the menu over, immaculate in a charcoal Dolce & Gabbana suit. She had started out trading forex for Credit Suisse, turned down a big position there to set up a fund concentrating on energy commodities. I’d put some cash in but that wasn’t why she sought me out. The mutual professional interest was enough to keep the sexual tension productive. She’d chosen the venue, which had just opened, she said. The place was bright, with wood and chrome, high ceilings and white-tiled walls like a butcher’s; light glinted everywhere you looked, as if you were inside a bubble. The menu swam in front of my eyes. I kept reading Experimental Cocktails. In Saudi Arabia that meant a bag of raw alcohol and a Coke.

We ate duck egg and asparagus, and seafood on ice. She insisted this was a thank you, which meant regularly topping up my glass, the bottle dripping water across crab shell. I’d given her a heads-up on Turkstream – a proposed line pumping gas under the Black Sea – and a Goldman Sachs fuck-up in Libya, which her fund had turned to profitable use if the crustacean still life was anything to go by. I hadn’t done it for the sake of a seafood platter but it was all part of the play.

‘Who’s big in Kazakhstan these days?’ I asked.

‘Chevron, Gazprom. PetroKazakhstan was bought by the Chinese last year. JP Morgan are trying to get hold of the financial sector. A lot’s still bound up in state-owned companies.’

‘Got a contact there? Someone who knows the scene?’