In the Mississippi River town of Natchez, a theatrical troupe led by Captain Andy Hawks performs on their show boat, the Cotton Blossom. His daughter, Magnolia, dreams of becoming a stage star but must contend with her mother's disapproval and the challenges of life on the river. Magnolia's world changes dramatically when she meets Gaylord Ravenal, a charming riverboat gambler. The two fall in love, marry hastily, and are given leading roles in the show.

As they embark on a life together, Magnolia and Gaylord face numerous trials, both personal and professional. They struggle with financial instability and Gaylord's gambling habit, which creates tension in their marriage. Meanwhile, Magnolia pursues her stage ambitions and battles to maintain her independence and resilience. Throughout their journey, themes of love, hardship, and social change weave through their lives against the backdrop of the evolving American South.