AllMovie

Romance of the Underworld was adapted from a barnstorming stage piece by Paul Armstrong. Forced by circumstance into a life of sin and deprivation, Judith Andrews (Mary Astor) ends up as a "hostess" in a seedy dance hall. She is rescued by her kind-hearted employer Stephen Ransome (John Boles), and together the newlyweds carve out a new and decent life for themselves. Their happiness is threatened when a figure from their past, slimy racketeer Derby Dan Manning (Ben Bard), tries to blackmail the unfortunate couple. In a climax that would not have been possible in the Production Code-dominated 1930s, Derby Dan is foiled by sympathetic detective Burke (Robert Elliot), who slyly arranges for the villain to be bumped off by one of his own underworld buddies.