‘Look,’ continued Luke, ‘I don’t like you, you don’t like me. We never have done. But come on! These aren’t your people, Squires. You’ve got way too much to lose. You’ve got a good life, a place in the country. Why would you want to get mixed up in this death cult?’

Hugo Squires had returned to his chair and he sat there, shaking his head in mock sadness. ‘You really don’t know a damn thing, do you, Carlton? I bet you don’t even know what “puts” and “calls” are. Well, do you?’

‘Enlighten me.’

Squires glanced at his watch. ‘They’ll be coming through that door any moment now so we haven’t got time for me to give you the full lecture. But I’ll make it easy for you. If you think the market is going to fall, you buy a contract called a “put option”. That gives you the right to sell an underlying stock at a certain price, the price it was before the market fell.’

Luke watched him explaining this with a rising sense of incredulity. There they were, sharing a room with canisters of a lethal pathogen, inside a warehouse peopled by fanatical, possibly suicidal far-right extremists. And this man in a Barbour jacket was calmly talking about the stock market.

‘A “call option”,’ explained Squires, really warming to his subject now, ‘is the reverse. If you think a stock or a sector is going up you buy a call option.’

Luke’s mouth fell open a fraction. Suddenly he got it. So that was why Squires was here. His motive wasn’t ideological at all. It was nothing of the kind. It was sheer, naked greed.

Squires picked up on his facial expression. ‘So you get it now, do you? That’s good. Elise always said you were smarter than you look.’

‘Let me get this right,’ said Luke, still wincing from the strain on his arms and wrists. ‘You’ve financed all this just to make money out of thousands of people dying from a virus?’

Squires looked positively pleased with himself. It made Luke sick to his stomach.

‘Not just me, Carlton. I really can’t take all the credit. There’s a small consortium of like-minded people who have … Well, let’s just say we’ve invested wisely. When this thing goes off it’s not hard to guess which stocks are going to plummet like a stone. In fact, even you could probably work that out, soldier boy.’

Now it was Luke’s turn to sneer.

‘You’re off your head,’ he told him. ‘You don’t honestly think no one’s going to notice your trades?’