Night Mail

The best-known film of the British documentary movement, made by the GPO Film Unit to celebrate the postal special that carried letters overnight from London to Scotland. The first two-thirds are lucid observation — mail bags sorted at speed, trackside apparatus snatching pouches without stopping — and the finale is the famous experiment: W. H. Auden's verse written to match the train's rhythm over Benjamin Britten's score, accelerating as the mail crosses the border. A film about sorting letters that became a small masterpiece. The film is in the public domain.