With this superb novel of suspense, le Carré changed the rules of the game. His story is one last breathlessly perilous assignment for the agent who wants desperately to end his career of espionage - and "come in out of the cold." Graham Greene said "the best spy story I have ever read."
Reading this partly in anticipation of Tinker, Tailor, Soldier, Spy and partly because I loved The Constant Gardener (the movie, anyway. I haven't read the book).