The one thing he knew for definite this evening was that he was too drunk to visit Holland. This was a problem, because he’d only felt more lost than right now once before during his MI5 career. The first time he’d visited the Gresham Arms. The first and only time he’d been responsible for a fellow officer’s death. And it had been Holland who had helped him find his way back then.

Holland had recruited Knox into the Service as his apprentice at the end of the war. Knox wasn’t a typical candidate for MI5. But Holland had been impressed by his military record, and even more so when he discovered that he’d lied about his age to sign up to the army a week after D-Day.

Holland had become Knox’s patron. Knox had become his pupil and, in turn, had recruited Jack Williams as his fellow disciple. Williams was Knox’s complete opposite. He was from the right kind of family and had gone to the right school. He had the relaxed, carefree attitude of the extremely well off, and the bright eyes and skin of someone who grew up breathing country air on land their family owned. But he also saw through his privilege and knew it was hollow, built on nothing he or his parents had achieved themselves.

His mother and father were content to while away their lives on their large Hertfordshire estate, enjoying the silver spoon that Williams’s father had had the luck to be born sucking on. Williams himself preferred to do something with his. When he was young, he used his money to travel, and his easy charm to make friends all over the world. Then, when it was time for more serious pursuits, he used his name to get into Sandhurst. His great-grandfather had been a brigadier in the early days of the Raj in India, and the army had a long memory.

Knox met Williams in Paris during the sombre yet heady days after its liberation from the Nazis. Williams was five years older than Knox, an officer in the 1st Royal Tank Regiment. He’d landed on Gold Beach during D-Day and had been in France ever since, pushing the Wehrmacht back village by village.

The proprietor of a small bistro on the Île Saint-Louis sat them together one night when they happened to arrive at the restaurant at the same time, both in uniform. Before Knox could point out that they didn’t know each other, Williams had asked the owner, in perfect French, for a good bottle of Cahors wine for them to share.

‘I’ll show you mine and you can show me yours,’ Williams said to Knox as their wine was delivered.

‘Excuse me?’ Knox asked, confused.