Aspiring songwriter Tommy Taylor pins his hopes on the promises of his employer, gambler and gangster "Chips" Maguire. However, Chips uses the gun he had registered under Tommy's name to kill Monks when he betrays Chips to the police. It turns out Chips had Tommy carry the gun for just such a situation, to provide him with a fall guy. Needing a place to hide out, Chips blackmails Tommy into taking him to the boarding house owned by his mother, Nora Taylor, and her longtime friend, Maggie Ryan, by threatening to turn the gun over to the police. Nora is overjoyed to see her son after an absence of five years. Tommy introduces them to Chips, who pretends to be a man named Grasselli recovering from a nervous condition. By chance, Maggie's showgirl daughter, Sarah Jane, returns the same day. The two mothers dream of their children getting married, but Tommy seems indifferent to Sarah Jane. Sarah Jane becomes suspicious of Grasselli, who does his best to avoid being seen. She eventually hides in the hall bathroom and recognizes him, having worked for him once. Unwilling to get Nora and Maggie in trouble, she agrees to keep Chips' secret. Nora starts mothering Chips, as does Maggie after a while. Tired of hiding in his room all the time, Chips emerges and becomes acquainted with the other boarders: Miss Flint, Mr. Salmon, washed-up magician The Great Boldini, and Mr. Van Diver. In the parlor, Chips enjoys an amateur show put on by Tommy, Sarah Jane, and the boarders. When Sarah Jane learns that Nora and Maggie are about to lose their house due to unpaid taxes, she turns to Chips for help, encouraging his attentions, even though she is in love with Tommy. He provides the money, but as that will only postpone their financial problem, he suggests that they set up the boarding house to bring in money by turning it into an exclusive nightclub, with the added advantage that Tommy and Sarah Jane can showcase their talents. Nora is enthusiastic, but it takes some persuasion to get Maggie to go along. In the meantime, Miss Flint sees Chips' picture in a crime magazine. Sarah Jane intimates that Chips will have her killed in a gruesome manner if she tells anyone what she knows. But on opening night, after drinking too much champagne, she becomes frightened by Chips' taunts and goes to the police station. Two detectives spot Chips in the nightclub, but agree to let him watch the rest of the show. Tommy sees the cops and assumes the worst. He goes to the roof to be alone. When Sarah Jane joins him there, he finally admits he loves her. She urges him to flee, but he refuses to run away. Though he can easily incriminate Tommy, Chips decides to confess to the murder, allowing the young lovers to make a clean beginning.
