But no one was perfect and Charles was persuaded that the Office would do better under Gareth than under any other in-house choice. He was also satisfied that his choice would have been the same even if he and Gareth had not been on friendly terms for years and had not, as younger officers, run operations together. Not that these days the choice of successor was any longer his; EU rules required that the post be advertised to outsiders and Whitehall might well decide that it would look more fashionably inclusive to have a woman, or someone from an ethnic minority or an out-to-grass politician to run Her Majesty’s Secret Service. But his view would still carry informal clout because of his relations with the cabinet secretary and the various departmental permanent secretaries who would decide the shortlist before recommending it to the foreign secretary and prime minister. So long as he didn’t make a mess of things in the meantime. Also, with Brexit the reign of EU rules was presumably coming to an end.

‘One thing I wanted to ask.’ The man lowered his voice and moved closer, with the exaggerated solemnity of a spaniel begging a biscuit. ‘These negotiations, this Brexit stuff – I hope we’re reporting on the buggers, their position papers, fallbacks and all that? Bloody well should be.’

It had become a frequent question since the Brexit referendum, easily answered. ‘Off-limits as far as Whitehall is concerned. They wouldn’t wear it. Spying on friends is politically more dangerous than spying on enemies. Anyway, the EU is so leaky we don’t need to; it all comes out in the wash. Maybe it’ll change after we’ve left.’

‘But they’re not our friends, they’re trading partners who are also competitors. Anyway, countries don’t have friends, they have interests. Can’t remember who said that. Applies even more to intelligence services.’

Charles was relieved to spot Sarah’s blue and white dress as she detached herself from the crowd and came across the lawn towards them. Luckily, he was spared the embarrassment of introductions. ‘Robin,’ she said, smiling and holding out her hand to the red-faced man, ‘we haven’t met since your retirement party. How’s retirement treating you?’

‘Sarah, how are you, lovely to see you. I was just saying to Charles, it’s taught me what I’ve long suspected . . .’