IN LONDON IT WAS TEN minutes past one, and Yuri Volkov was running a few minutes behind schedule. Officially, Volkov held a low-level post in the consular section of the Russian Embassy. In reality, he was a senior operative at the SVR’s London rezidentura, second only to the rezident himself, Dmitry Ulyanin. British intelligence knew the true nature of his work, and he was the target of regular physical surveillance by MI5. For the better part of an hour, Volkov had been attempting to shake a two-person team from A4, a man and a woman posing as husband and wife. Now, as he moved along the crowded pavements of Piccadilly, he was confident he was finally alone.

The Russian crossed Regent Street and ducked into the Piccadilly Circus Underground station. The station sat astride both the Piccadilly and Bakerloo lines. Volkov fed a prepaid fare card through the scanner and made his way down the escalator to the Bakerloo platform. And there he spotted the asset, a weak-chinned balding man in his late forties wearing a department-store suit and a mackintosh coat. He was the sort of man that young women instinctively avoided on the Underground. And with good reason, thought Volkov, for young girls were his vice. The SVR had found one for him, a child of thirteen from some shithole in Siberia, and they’d fed her to him on a plate. And now they owned him. He was a mere cog in the vast machine of intelligence, but important matters routinely crossed his desk. He had requested a crash meeting, which meant that in all likelihood he had an important piece of intelligence to pass along.

An overhead sign flashed to indicate the approach of a northbound train. The man in the mackintosh moved to the edge of the platform and Volkov, ten paces to the left, did the same. They stared straight ahead, each into a private space, as the train eased into the station and expelled a crowd of passengers. Then both men entered the same carriage through different doors. The man in the mackintosh sat, but Volkov remained standing. He moved to within five feet of the man, an appropriate distance for secure transmission, and seized hold of a handrail. As the train lurched forward, the man in the mackintosh removed a smart phone, thumbed the touchscreen a few times, and then returned the phone to his pocket. Ten seconds later the device in Volkov’s breast pocket pulsated three times, which meant the information had been transmitted successfully. And then it was done. No dead drops, no face-to-face meetings, and it was all entirely secure. Even if MI5 managed to capture the spy’s phone, there would be no trace of the activity.