Mr. District Attorney is a 1941 American comedy film directed by William Morgan and written by Karl Brown and Malcolm Stuart Boylan. The film was based on the long running and popular radio series Mr. District Attorney. It stars Dennis O'Keefe, Florence Rice, Peter Lorre, Stanley Ridges, Minor Watson and Charles Arnt. The film was released on March 27, 1941, by Republic Pictures.^[1][2][3] It was followed by a sequel Mr. District Attorney in the Carter Case later in the year, with different actors in the leading roles.

A well-connected and well-educated young lawyer P. Cadwallader Jones gets an appointment as deputy district attorney through the influence of his uncle. After embarrassing his superior in court, he is punished by being assigned a seemingly unsolvable cold case concerning a notorious embezzler who has been missing for four years. However, with the assistance of a streetwise young female journalist he soon begins making inroads into the mystery.

• Dennis O'Keefe as P. Cadwallader Jones
• Florence Rice as Terry Parker
• Peter Lorre as Paul Hyde
• Stanley Ridges as District Attorney Tom F. Winton
• Minor Watson as Arthur Barret
• Charles Arnt as Herman Winkle
• Joan Blair as Betty Paradise
• Charles Halton as Hazelton
• Alan Edwards as Grew
• George Watts as Judge White
• Sarah Edwards as Miss Petherby
• Helen Brown as Mrs. Paul Hyde

• Mr. District Attorney in the Carter Case (1941)
• Secrets of the Underground (1942)