Based on a play by Owen Davis, a willful southern belle loses her fiancé and causes a duel before an epidemic carries off the man she loves.
In 1852 New Orleans Buck Cantrell (George Brent) quarrels with De Lautruc and is challenged to a duel. Julie Marsden (Bette Davis) arrives late to the party in her riding habit. She is engaged to banker Preston Dillard (Henry Fonda); but Buck says she won't like the North. Preston urges directors about railroads and won't leave the meeting for Julie's dress fitting. So Julie chooses a red dress, defying the convention of unwed women wearing white. Dr. Livingstone (Donald Crisp) tells Pres his father would have whipped Julie. Pres takes a whip but kisses Julie. He says she can't wear a red dress or he won't go. Julie sends for Buck and asks if he killed de Lautruc. Buck won't take her to the ball in a red dress either. So she gets Pres to take her by implying he is afraid of defending her. At the ball Julie and Pres are politely shunned. Julie wants to leave, but Pres dances with her. When Pres says good-bye, she slaps him. Aunt Belle Bogardus (Fay Bainter) calls Julie a fool and says Pres won't come back.
One year later yellow fever is worse. Belle tells Dr. Livingstone that Julie won't go out and tells Julie that Pres is coming home. Julie goes to Halcyon plantation and hopes to marry Pres. Buck and General Bogardus (Henry O'Neill) arrive and tell Belle of fever laws. Pres arrives with his wife Amy (Margaret Lindsay). Julie wears white for Pres and asks his forgiveness but then meets his wife. Julie thinks and is glad to see Buck, who at dinner suggests hanging abolitionists. Pres says that Northern machines will defeat slave labor. Pres learns from the slave Cato (Lew Payton) that Julie has not been seeing anyone. Outside Julie tries to win Pres back, but he rejects her kiss. Buck comforts Julie and argues with Pres, who is called to the city. Ted Dillard (Richard Cromwell) objects to Buck arguing with Amy. Julie tells Buck not to fight Ted, and she asks Ted to apologize; but Ted asks Gen. Bogardus to make the arrangements. Belle tells Julie that women can start men quarreling but can't stop them. In the duel Ted kills Buck, and then he blames Julie. A man is killed for running the fever line, and Julie welcomes all the guests to stay.
Pres and Dr. Livingstone see fever devastating New Orleans. Pres drinks and hears that Ted killed Buck. Pres faints, and no one will help Dr. Livingstone carry him. At dinner Cato says that Pres got the fever. Julie tells Gros Bat (Eddie Anderson) to take her through the line, and she finds Dr. Livingstone with Pres in her house. She nurses Pres to keep him cool. Gen. Bogardus, Belle, Ted, and Amy arrive in a carriage after getting a pass and find Julie with Pres. Dr. Livingstone says he reported Pres, who will be taken to the lepers' island. Amy asks him to let her go too. Julie tells Amy that she could fight better for Pres and asks to go in her place to redeem herself. Amy asks Julie who Pres loves, and Julie says he loves his wife. Amy lets Julie go with Pres.
This melodrama reflects the peculiar values of ante-bellum Southern society in which arrogance, willfulness, and stubbornness multiply problems into major tragedies.