Opposite him sat Ian and Kate. Sir Alan was at the end of the table, beneath an enormous watercolour of a Cairo street market. Kate recognized, but could not quite recall, the artist. As in so much of the rest of his life, Sir Alan had exquisite taste in art.

‘I’m very sorry to force you to meet like this,’ Meg Simpson said. ‘Kate, you take the floor.’ Like the rest of them, Sir Alan had no wish to extend the meeting a second longer than was necessary.

‘You asked for more evidence,’ Kate said, facing the foreign secretary, ‘so I activated a source whom I believe to be completely reliable. At considerable personal risk, he agreed to travel out of Russia to meet me near Helsinki in Finland. We talked for about an hour and he confirmed, in essence, what Mikhail, Igor’s son, told me in both Venice and Berlin.’

‘What do you mean, “in essence”?’ Simpson asked.

‘He was honest about what he didn’t know. He couldn’t be certain of exactly what had happened in terms of the internal dynamics of the very top tier of individuals close to the Kremlin. But he confirmed that Vasily Durov and Igor Borodin were under house arrest and that the widely held view was that the Kremlin had concluded both they and the SVR in general were becoming too arrogant and over-mighty.’ Kate stared at the spotless oak table before her.

‘So he confirmed the GRU had been engaged in some kind of coup against its rivals in the SVR?’ Simpson asked.

‘Yes.’ This lie was coming harder than she’d imagined. Kate studied her hands. There was a long silence. She finally looked up and watched the faces around her. A grim group they assuredly were. Surprisingly – or maybe not, given the relentless nature of his ambition – Ian was the first to break ranks. ‘This really leaves us with no choice, Foreign Secretary. I’ve had my reservations. You know that. But this is crystal clear: a reliable agent, talking to one of our most experienced and able officers. We have no choice but to pursue this to its logical conclusion now.’

Simpson gave him a withering stare, but he didn’t back down. If this was to go ahead and ruin a prime minister, he wanted to own it. ‘My advice is that we must proceed with all due speed.’ My advice. He made it sound like the most weighty and significant thing in the world. Meanwhile, Sir Alan gazed out of the window.

‘It doesn’t assuage any of my doubts,’ Simpson said. She was visibly squirming now. She’d taken her glasses from around her neck and was tapping them nervously against her knee.

They waited her out. ‘If the video is fake, the ramifications are horrific. Your source can’t verify it, can he?’