Just before the audit came in, I managed to jump ship with Floyd’s help, becoming an independent consultant. Things were tight for a little while, and Alice and I had to cancel our plans to buy our first house. In the end, we were priced out of San José anyway, so when a job came up back in the UK I grabbed it while I could.

In some ways, the move back across the Atlantic was easier for Alice than it was for me. English by birth, she had never been comfortable with the dry, hot Californian weather, whereas I, after too many years enduring rain and long, dark winters in our student days, had grown to love the West Coast weather.

Meanwhile, amidst all the furore around GreenTech, Marlon and Herschel quietly vanished without trace.

‘We know they had help.’ It was a different restaurant, this time on a rainy Saturday afternoon, in London. The people around us had Selfridges bags piled against their tables like sandbags around machine-gun nests. A thin grey drizzle carved tributaries through layers of dirt streaked across a street-facing window. I hadn’t seen Floyd in two years.

‘From who?’ I asked. ‘Red Harvest?’

‘Who else?’ Floyd gave me a look. ‘Which brings me to why I’m here.’

‘Ah.’ I looked down at my steak tartare. ‘No such thing as a free lunch, right?’

He smiled at that. ‘Just before GreenTech’s directors went before the board of inquiry, some gene cultures went missing.’

‘You think Marlon and Herschel took them?’

The way he looked at me made me wonder if he’d had special training in how to make people feel there was nothing they could possibly hide. ‘That’s my belief, yes.’

‘Why would they do that?’

‘That’s where you come in. Your calendar is free for the next five weeks. You’re not due to take part in another consultation until at least March, and you won’t even have to travel that far from home.’

How do you know all that? I almost asked him, then let it go. I had the same, unsettling feeling I’d had when Floyd had first remade my acquaintance.

I promised to make careful enquiries. I tracked down another former colleague from GreenTech, with Floyd’s help. From him, I learned that the missing cultures had been ordered to be destroyed. Perhaps Marlon and Herschel had indeed done this, but Floyd clearly thought otherwise.

The third and last time I met with Floyd was in a pub we had often frequented, and which was still popular with other American students studying at Oxford. I had taken the train up, hoping this might be the last time Floyd required my services.