A minor Poverty Row mystery melodrama, Million Dollar Mystery featured former matinee idol James Kirkwood as a gangster falling in love with the daughter (Lila Lee) of a reformed colleague. As it turns out, Kirkwood is in reality a Secret Service operative in disguise and is soon in possession of enough evidence to bring the gang to justice. Kirkwood and leading lady Lee were married at the time, the union producing James Kirkwood, Jr., the creator of Broadway's long-running A Chorus Line. Penned by Trem Carr Productions' house writer Arthur Hoerl, Million Dollar Mystery had no connection to the 1914 Thanhouser serial The Million Dollar Mystery.