Based on the musical by Jerome Kern and Oscar Hammerstein II from Edna Ferber's novel, the daughter of a show-boat captain becomes a singer and marries a gambler.
As the show-boat performers parade, Steve (Donald Cook) is jealous of his wife Julie LaVerne (Helen Morgan) and fights Pete (Arthur Hohl). Gaylord Ravenal (Allan Jones) meets Magnolia "Nola" Hawks (Irene Dunne), and they sing "Only Make Believe." Joe (Paul Robeson) sings "Ol' Man River." Nola talks to Julie about love. Julie sings "Can't Help Lovin' That Man," and Queenie (Hattie McDaniel) and Joe join in. Pete tells the sheriff about Julie. Steve cuts Julie's finger and sucks her blood. The sheriff accuses Julie of miscegenation, being a Negress married to a white; but Steve says he has Negro blood in him. Mrs. Parthy Hawks (Helen Westley) tells Steve and Julie to go. Gaylord comes in, and Captain Andy Hawks (Charles Winninger) hires him to act. Nola pleads for Julie but is given her role. Gaylord acts the love scene and kisses Nola. Frank Schultz (Sammy White) wants to marry Ellie (Queenie Smith). Gaylord sings "I Have the Room Above Her," and Nola answers. Parthy shows Andy a letter from Pete about Gaylord.
During the play a backwoodsman (Stanley Fields) shoots at the villain, and so Andy hilariously plays several parts to finish the story. In black face Nola sings "Gallivantin' Around." On deck Gaylord asks Nola to marry him the next day, and they sing "You Are Love." Parthy says that Gaylord is a murderer, hears of the wedding, and faints. Queenie criticizes Joe for being lazy, and he sings "I Still Suits Me." Joe goes to get a doctor for Nola, while Gaylord plays poker. Andy calls the baby girl Kim.
Gaylord takes Nola to Chicago, wins gambling, and buys a car. Andy reads a letter to Parthy. Ellie and Frank find Nola owing rent. Nola gets a letter that Gaylord has left, and she cries. Gaylord goes to the convent to see Kim and says good-bye, singing "Only Make Believe." Frank takes Nola to a theater; they wait outside as Julie sings "Bill" and is told by Green to be sober. Frank asks Green to hear Nola, who sings "Can't Help Lovin' That Man." Julie hears her and leaves. Green has Nola sing ragtime. On New Year's Eve Andy takes women to a show. Frank and Ellie sing and dance. Frank tells Andy that Gaylord is gone. Nola sings "After the Ball." Nola's singing career takes her to New York and London. Years later Nola retires, and Kim sings. Kim stars on Broadway, while old Gaylord works at the stage door. Nola finds Gaylord, and they watch Kim. Gaylord slips out. Kim has Nola sing "You Are Love," and Gaylord joins her.
Fine songs, writing, acting, and directing make this musical excellent entertainment. The story portrays the injustice of race prejudice and the sad consequences of alcoholism and a gambling addiction.