The film holds you from the very first frame with the excellent music by Sol Kaplan and the strains of alto saxophone. The film is made on the exciting novel of John Le Carre. Richard Burton deserved an Oscar for his performance here as a disillusioned and dispirited British agent. He is made to act as an undercover agent behind the Iron Curtain - East Germany. His defection is staged but it goes sour as he is arrested and humiliated. He is actually used as a pawn to get a double agent reinstated in Berlin. The camera work by Oswald Morris creates an impact on the film in black and white. The film is very well directed by Martin Ritt. Claire Bloom plays a British communist who loves Alec Leamus (Burton)during the undercover operation phase. The double crosses are so well plotted by Le Carre who also wrote the screenplay for the film. Oskar Werner has played well as Fiedler and so has Peter Van Eyck as Hans Dieter Mundt.