George Smiley, the central character of Tinker, Tailor, Soldier, Spy and many other John Le Carré novels, is a careful, methodical man. He has a keenly analytical mind and he almost never overlooks, or even forgets, the smallest detail. Smiley’s nemesis is the Soviet agent known only as Karla. In this novel, Smiley recalls one of his few meetings with Karla, and a detail of that meeting leads to uncovering the double agent. Smiley comes out of retirement to help catch this mole; his contribution becomes crucial because Control, the former head of their intelligence unit, the Circus, has died. Control had bestowed the nicknames on the agents. Smiley’s weakness is his wife, Ann. It is on this weakness that the plot turns.

Percy Alleline became head of the Circus on Control’s death. Proud and aloof, he is determined to ferret out the mole, but Smiley still suspects him. Conscientiousness is his strength, but ambition is his weakness.

Bill Haydon is vain and charming. His strength is smooth duplicity, and his weaknesses are materialism and sex.

Ray Bland is the most academic of the bunch. His strength is his deep scholarly knowledge of the Balkans; his weaknesses are his lack of awareness and political savvy.