After the confetti of memoranda and demands for speed, Sir Alistair knew that the location of the leak, coupled with the timing, would increase rather than diminish the pressure. It was like sailing out of the fog and seeing the rocks only yards away.

Sir Berkeley Naire-Hamilton hurried fussily across the office to meet him, hand outstretched. ‘Good to see you, my dear fellow. Good to see you.’

‘And you,’ said Wilson.

‘I’ve tea. Earl Grey, I’m afraid. All right? You’ll take it with lemon, of course?’

The man bustled around a side table where the tea things were set, asking the questions automatically without any wish or expectation of a reply.

Wilson accepted his tea and, instead of returning to his ornate, over-powering desk, Naire-Hamilton seated himself opposite the director on a matching, wing-backed chair.

‘Delighted to hear there’s a breakthrough,’ he said.

‘I’m not sure you will be,’ warned Wilson.

‘What do you mean?’ demanded the permanent civil servant. Naire-Hamilton was a florid-faced, balding man, a rim of tightly clipped white hair hedged around his face. There was the hint of a minor stroke or some facial paralysis, which had caused the left-hand side to collapse slightly, making one eye more pronounced than the other. Naire-Hamilton had a tendency to the flamboyant, with broadly striped suits and pastel shirts with matching ties. It went with the vague foppishness of the office. It was traditional Whitehall, like bowlers and striped trousers with black jackets and vintage Dow with Stilton. The furniture was predominantly Georgian, bulbous-calved with a lot of leather, and there were ceiling-to-floor bookcases with volumes that couldn’t easily be removed because they’d remained unread for so long that the covers were stuck edge to edge.