In 1875, Clio Dulaine, the illegitimate daughter of an aristocratic New Orleans Creole man and a French woman, returns from Paris to her birthplace in Rampart Street to avenge her mother's mistreatment at the hands of her father's family, the Dulaines. Years ago Clio's mother accidentally killed Dulaine when he tried to prevent her from committing suicide, and the scandalized Dulaines then exiled Clio and her mother to Paris. Clio is accompanied by her mulatto maid, Angelique, and her dwarf manservant, Cupidon. After fixing up the rundown house in Rampart Street, Clio ventures out, hoping to encounter the Dulaines. At the French marketplace, Clio stops for a bowl of jambalaya and is immediately attracted to Clint Maroon, a tall Texan in a white hat, who is eating at the counter. The attraction is mutual, and Clint offers to drive Clio to the cathedral in his carriage, but a disapproving Angelique interferes, and Clio leaves without him. After the service, Clio, Angelique and Cupidon breakfast at the restaurant patronized by the Dulaines every Sunday. Announcing to the maitre d' that she is a relative, Clio sits at the table reserved for the Dulaines, but when the Dulaines arrive, they recognize her by her resemblance to her mother and leave without a confrontation. Clint and Clio meet again at the restaurant, and afterward, he drives her home. Eventually, Clint moves into Clio's house. Although Clio and Clint are in love with each other, Clio, who is obsessed with her plans for revenge, intends to marry a rich and powerful man to prove that she is as good as her father's family. Clint, a gambler, who never intends to marry, is out for revenge on the railroaders who ruined his father in Texas. While Clio continues to embarrass the Dulaines at every opportunity, planning, if necessary, to interrupt the debut of her half-sister Charlotte, Clint, exasperated by Clio's unrelenting machinations, leaves for Saratoga. As the result of Clio's scheming, the Dulaines pay her $10,000, agree to destroy the Rampart Street house and bury her mother in a New Orleans cemetery. Later, Clio joins Clint in Saratoga, where she plots to marry wealthy railroad heir Bartholomew Van Steed. Clio's arrival with Angelique and Cupidon causes quite a stir, and because the hotel is completely booked, Clint, who is now calling himself Colonel Maroon, offers Clio two of the rooms in his suite. Privately, he explains that Bart owns a railroad, the Saratoga Trunk, which is suddenly worth millions of dollars because it connects the coal country with New York. Railroader Raymond Soule, the same man who ruined Clint's father, is trying to steal the railroad from Bart. Clio poses as the widow of a French count, a claim that many doubt until she is unexpectedly backed up by socialite Mrs. Coventry Bellop, who intensely dislikes Van Steed's mother. Clio's beauty and melodramatic posturing quickly capture Bart's attentions. In the meantime, Clint offers to save the Saratoga Trunk from Soule in exchange for shares in the railroad. When Clio learns that Bart is paying Clint to do his dirty work, she hysterically accuses him of cowardice and sends him away. This excites Bart, who explains that he knows about her background, but wants to marry her anyway. The costume ball that evening is interrupted by the arrival of Clint and Cupidon, who were seriously wounded during a pitched battle with Soule's men. Clio realizes that she loves Clint too much to marry another man and nurses him back to health. Clint then tells Clio that, having saved the Saratoga Trunk from Soule, his railroad shares have made him a very rich man.