According to the brief and rather gruff precis Holland had given Knox, the SLO—who had only been in Ottawa for six months—had been tricked into believing the Ralliement National, a right-wing political party campaigning for independence in Quebec, was secretly being funded by the Soviets. When he escalated it, the KGB claimed innocence, and the Ralliement National exclaimed their offence at British interference in their affairs both officially and loudly. Political tensions across Canada increased, and MI5 had egg on its face, which was exactly what the KGB had intended.

Knox watched the small ferries dance their way across the calm of the harbour. Every ten minutes or so a seaplane momentarily interrupted their ballet. He watched six come and go, cutting direct lines between the dock and the outer harbour where they had a long enough stretch of water to take off and land. None of them were Northcott’s.

Knox had been given the make and registration of his seaplane in Ottawa and, when he’d pointed out that he wasn’t an aviation expert, a description too. He was looking for a yellow fuselage with a pair of vivid turquoise wings strapped across the top of it. Northcott, he was told, was hard to miss.

Finally, just as Knox was beginning to consider retreating back into The Empress he spotted a flash of bright blue turn into the inner harbour.

He walked down to the floating jetty as the seaplane pulled alongside it, cut its engines and stopped its twin rotor blades spinning. The door of the cockpit opened and Knox got his first proper look at Sir Guy Northcott. His file photo in Leconfield House had shown a fairly unremarkable businessman in his late sixties with neat hair, clean-shaven, wearing a sombre, expensive-looking suit. The man climbing down the steps cut into the side of his plane looked the complete opposite. His long, grey hair was slicked back from his heavily bearded face, and he wore a thick, roll-neck jumper. He looked like he should be crewing a fishing trawler somewhere in the North Sea.

Another man followed him out of the plane. He was another opposite. Where the older man looked relaxed, confident in his own skin and world, his younger companion seemed utterly terrified. He was thin, almost frail, his hair roughly cut short against his skull. He couldn’t have been a day over twenty, and his wide eyes darted round, looking for signs of danger in everything they saw. He wore frayed slacks and a thin leather jacket, and held a canvas duffle bag to his chest.

‘Sir Guy?’ Knox said, pulling his hand out of his coat pocket and extending it towards Northcott.

‘It’s a while since anyone called me that,’ Northcott replied, shaking Knox’s hand as an easy smile creased the skin at the edges of his mouth and eyes.