A double bill containing both the French and German versions of 'The Threepenny Opera', based on the musical play by Bertolt Brecht and Kurt Weill. In 1890s London, underworld king Mack the Knife decides to marry Polly, daughter of Peachum, king of the beggars. The beggars object to the union, and cause a revolt. Director G.W. Pabst planned a third, English version of the film, that was never completed.