The Man in Search of His Murderer () is a 1931 German comedy film directed by Robert Siodmak and starring Heinz Rühmann, Lien Deyers and Hans Leibelt. The film is partially lost; of the original 9 acts, only five (50 minutes) remain. It was one of the early leading roles for upcoming German star Heinz Rühmann. Co-writer Billy Wilder was at the beginning of his long career. It was shot at the Babelsberg Studios in Berlin and premiered at the city's Gloria-Palast. The film's sets were designed by the art director Robert Herlth and Walter Röhrig. It was remade in 1952 as You Only Live Once.