Synopsis by Janiss Garza
After supporting a number of male luminaries, Louise Lovely began her own relatively brief and undistinguished starring career. The tired plot to While the Devil Laughs, her first headlining vehicle, made for an inauspicious debut. Mary Franklin (Lovely) has a drunken father (Wilson Hummell), an invalid mother (Molly Shafer), and a kid brother (Coy Watson, Jr.) and sister (Helen Field) to support. To make ends meet she is works as a hostess in a sleazy cafe, where she steals jewelry from her dancing partners. She is engaged to Billy Anderson (William Scott), a fellow crook who has invented a dishwashing machine. Now that he has had it patented, he plans to go straight, and wants Mary to do so, too. Gus, Mary's little brother becomes seriously ill and Mary promises God she will quit her life of crime if the boy is cured. He recovers and Mary sticks to her word. But Pearl (Oleta Ottis), the wife of her former boss, "Fence" McGee (G. Raymond Nye), frames Anderson, who is jailed for six months. Mary can't find work and her mother dies. When Anderson gets out of jail, he swears vengeance. Mary's father starts a fire in his attempt to make home brew and Anderson is caught in the blaze. Mary rescues him, and Pearl confesses to her lies. Anderson's invention is sold, and he and Mary wed.