John le Carré's enigma is masterfully told by David Cornwell in 'The Pigeon Tunnel'
The documentary is a stream-of-consciousness exercise where le Carré, an eloquent raconteur and a witty mimic, is at his best. He is both the interviewee and the string-puller, forcing his audience to think, question, doubt, and almost forget that he is the one being interrogated — sorry — interviewed.