The Third Man
A truly melancholy film, in two distinct parts. First, we follow an enjoyable mystery, hunting down leads. Then it transforms into a tragedy in which the hero has to kill his best friend and lose the woman he loves, while the zither continues to wryly observe the events with its jaunty, indifferent tune. War has broken the world into shards and fragments (Dutch angles anyone?), and Holly finds himself an empty soul.