Peter Guillam, staunch colleague and disciple of George Smiley of the British Secret Service, is living out his old age on the family farmstead on the south coast of Brittany when a letter from his old Service summons him to London. His Cold War past has come back to claim him. Intelligence operations that were once the toast of secret London are to be scrutinised under disturbing criteria by a generation with no memory of the Cold War and no patience with its justifications.