It is, quite simply, the finest movie ever made.
The bare plot of "The Third Man" doesn't seem like much: An American, a writer, comes to postwar Vienna and discovers that his friend has died. As the American unravels the story behind the death, it soon becomes apparent that the man was murdered. The American falls in love and, in the end, learns a little about love and loyalty--too late, alas, to help himself.
But that doesn't begin to tell you that each shot in this movie is framed so lovingly, so meticulously as to look almost like a painting; or about the wonderful script, by Graham Greene, a marvel of wit and intelligence; or the performance by Joseph Cotten, often a leaden actor but at his finest here, and a short performance by Orson Welles so memorable that his face and voice and that ironic smile stay in the mind's eye long after the movie ends. Even the music, played on one lonely zither, is achingly beautiful.
There are enough fine moments here to make 10 lesser films. And the ending will break your heart without one false note or sappy cliche.