He ran his tongue along his teeth. ‘If he pulls out now, it would be an enormous loss of face for the Nigerians, and it might lose us all the influence we’ve earned in the last couple of years. And it was hard earned, believe me. But more importantly, it would deprive us of the opportunity of finding out what the hell the Russians are up to - and perhaps finding this traitor. That’s why we’re both here, after all.’

‘Doesn’t the traitor become a slightly lower priority now that the PM’s life is at risk?’

He tilted his head and let the way I had phrased it settle. ‘If there was a plot to kill the PM,’ he said, eventually, ‘it would seem to have been extinguished.’ He pointed at the rifle. ‘We even have the weapon they were going to use.’

‘They’re not going to call it off because of that!’ I said. ‘Golf Course Man had written down the name of the place he was to pick up the gun. No professional would do such a thing unless they had to. He must have been the back-up.’

He considered this for a moment. ‘Where’s the original sniper gone, then? And what weapon will he use?’

‘I’ve obviously no idea where they are, but weapons are easily replaceable.’

‘Yes. So are prime ministers.’ He misinterpreted my look. ‘Oh, don’t wet yourself. If I thought for a second we were endangering the life of the PM, I wouldn’t joke about it. I agree that there seems to be a wider plot, but it can’t be a coincidence: it’s surely linked to Slavin’s decision to defect. As Slavin is dead,’ - he pursed his lips at me - ‘he can’t tell us how, but we need to find out because it may help identify the traitor. And that is paramount: as long as he is operating, we have no idea how much damage he has done, or even in what areas. If we tell Cabinet Office about this, they’ll either whip the PM out of the country before we can blink, or wrap him so tight in cotton wool the Russians will immediately smell a rat. Either way, they will roll up whatever it is they’ve got going, and you’ll be no closer to finding out what Slavin knew or how it connects to the double.’

It was a beautiful speech. The twist in it was lobbed in so elegantly that it took me a second to catch up to it.

‘Me?’ I said.