Probably the best espionage thriller ever made, The Third Man has virtually everything going for it. Tremendous and appropriately stylish direction, astounding acting across the board, a great sense of humor, wonderful dialogue, and a great sense of sadness and loneliness that lends the story a great deal of weight. The opening scenes, quickly establishing the setting and danger, are masterful examples of tight and minimal exposition. And the ending is perfect - sad and cynical in just the right way. It's the best possible ending to one of the most flawless films ever committed to celluloid.