This glorious film is a true classic, and a historic document as well as marvellous cinema, with its footage of post-War Vienna, a divided and unhappy city beginning to come to terms with itself. Everything about it is memorable - the naggingly catchy zither tune by Anton Karas which opens it (the Harry Lime theme), the eerie black and white photography, Graham Greene's excellently mysterious plotline, and in particular the performances, not so much of Joseph Cotten, who is fine and doesn't let the side down, as of Trevor Howard trying to make good British sense of an out-of-control situation, Alida Valli as Lime's doomed, tragic, world-weary, stunning girlfriend and Orson Welles as Harry Lime himelf, one of the most memorably delayed entries in all cinema, seductive and sinister at the same time. It is beautiful to the eye and completely compelling, one of the very great films.