And Andrew had outlined another problem: the settlement of Incisor’s debts had not seemed to alter the impression they had of a man under severe pressure in more ways than one. Three weeks after he’d been made operational, they had grown sufficiently concerned that von Braun had been compromised that both he and Jilly – who had also met Incisor – were sent home. They had since communicated solely in the pre-agreed way and had avoided all face-to-face meetings. The intelligence had slowed to a trickle.

‘So he’ll be bloody nervous,’ Andrew had told her. ‘You’ll have to offer him immediate free passage if you’re going to ask him anything that is remotely dangerous or difficult. I don’t think there’s any chance he’ll accept unless the prospect of release from his torment is immediate.’

That made sense, but Kate had known damned well there was no prospect of her or her team arranging a difficult and dangerous extraction at such short notice. She’d eventually forced Andrew to admit that he had a plan, as she’d known he must. He’d said he couldn’t possibly go through with it without help from London: he just didn’t have the resources. She’d persuaded, then wheedled and in the end almost begged. And he’d finally agreed, provided he had her promise it was ‘with the prime minister’s full authority’.

She had no doubt Andrew would extract a price at some point down the line and she didn’t blame him. She was about to plunge in with size ten boots and blow up an agent and operation that might well have been the sum total of his work in post, with the credit and benefits not guaranteed to accrue to him or any of his team.

It had been a lot to ask.

They’d almost reached Smolensk now, the sun setting behind the blue and gold dome of a Russian Orthodox chapel in the corner of a flat wheat field. ‘We should get something to eat,’ Kate said.

‘I thought you were never going to speak,’ Grove replied.

‘Sorry, had a lot to think about.’

They had the only phones they’d brought with them powered down, the batteries out, so Kate took out a map and guidebook – their cover story was that they were tourists, after all – and navigated them to a restaurant called Temnitsa by a section of the fortified walls of Old Smolensk, just next to the Dnieper river.

Inside, it looked like an old Russian merchant’s house, a solid brick structure with high ceilings and ornate furniture. They were offered a table in front of a giant fireplace with an enormous oak lintel and red-brick surround. The fire was not lit, but a row of candles above it burned brightly. It was a romantic setting, which was not quite the mood Kate had been striving for. ‘You think he’ll live?’ Grove asked, as they surveyed the menu.

‘Who?’

Grove looked at her, puzzled. ‘Navalny.’

‘Oh, yes.’ The big news that morning had been that Russia’s main opposition leader had been poisoned on a flight from Siberia, then rushed to hospital. It didn’t take a detailed knowledge of world affairs or Russia to identify the culprit.