What is the connection between Maria Ostrakova, a Russian exile living in Paris, and the brutal murder in London of General Vladimir, an émigré Soviet General and former British agent? Spymaster George Smiley is summoned from his retirement to investigate.

Smiley finds out that his nemesis, the dreaded Soviet spymaster Karla, is harbouring a deep secret involving his personal life. In Hamburg he tries to track down Vladimir's assistant, Otto Leipzig.

Smiley gets into trouble with his superiors whilst in Hamburg, but he leaves the city with valuable information. He now needs to get Maria Ostrakova to safety.

Otto Leipzig is dead, but after Kirov's confession the trail becomes clearer, and Smiley finds himself travelling to Switzerland.

With information gained from Russian ambassador Grigoriev and a meeting with the elusive Alexandra, the scene is set for Smiley's final confrontation with his arch enemy, Karla.