In 1857 Missouri, Quincy Drew and Jason O'Rourke operate a successful confidence game in which Quincy, who is white, repeatedly sells Jason, who is black, as a slave. Although Jason was born a free man in New Jersey, he assumes a Southern slave's demeanor to make their ruses believable, then later escapes and meets Quincy outside town to split their profits. Despite their success, Jason is tiring of the game, and after he and Quincy encounter the ruthless slave hunter Plunkett leading a group of chained black men and women, Jason insists that they stop. Quincy, who is also unnerved by Plunkett, reluctantly agrees, but only after they try one more job across the state line in the Kansas Territory. At the first Kansas town, they find themselves in the throes of the hotly contested referendum over Kansas' admission to the Union as a slave or Free State. Because Jason is not allowed to sleep inside the town hotel, he grudgingly goes to the town livery, where a pretty young black woman named Naomi is amused to see him chaining himself to a post. Jason is attracted to Naomi and saddened when she reveals that she is being sold because her young master, with whom she played as a child, was ordered to sell her by his new wife. Meanwhile, as Quincy takes a bath, a woman who earlier picked his pocket tries to steal the rest of his belongings. She pretends not to know him, but finally relents and introduces herself as Ginger, a fellow con artist and kindred spirit. The next day, Jason asks Quincy to bid up to $1,000 to buy Naomi, which he does, telling Ginger Naomi is Jason's birthday present. Just before Jason is sold, notorious abolitionist John Brown gallops into town with a band of supporters, quickly gathers all the slaves into wagons, then rides out of town. In the chaos, Ginger disappears, after which Quincy follows the wagon tracks. While stopped by a stream, Quincy is accosted from behind by an Indian, who turns out to be Jason, spewing sounds he thought sounded like Indian words. The two men start to bicker about their situation and decide to split their money but find that Ginger has taken their money and replaced it with a derisive note. Not wanting to stay in Kansas, Quincy convinces Jason to back go to Missouri for one last chance to recoup their losses. As they try the game in the town of Bitter End, they again see Plunkett, who recognizes them and bids on Jason. Although Quincy tries to avoid selling Jason to Plunkett, Bonner, the man who had bought Jason in Dirty Shame, suddenly arrives to say that he is Jason's rightful owner. A brawl erupts, resulting in Jason's being sold to Plunkett by Bonner and Quincy being put in jail. Some time later, Jason finds himself chained in the livery next to Naomi, while Quincy is visited in jail by Ginger, who pretends to be his abandoned pregnant wife. Clutching Quincy to her, Ginger slips the jailer’s keys into his pocket, along with some money and a small gun. After Quincy escapes and meets Ginger, she reveals that she read about their capture in the newspaper and decided to help. Quincy then relates all of the various confidence games that he and Jason have run over the years, and says that he will find Jason, no matter how long it takes. He and Ginger then agree to be partners. Two months later, Plunkett has taken Jason and Naomi to Texas, where they are sold to Calloway, a wealthy plantation owner. Because Calloway seems kind, Jason tells him that he was born a free man and appeals to his fairness. To his shock, Calloway tells him never to speak like that again and orders him whipped. Meanwhile, Ginger and Quincy search for Jason by assuming guises as a medical team or missionaries searching for a slave carrying a mysterious and highly contagious “spasmodic lung pest infestation.” As the months pass, under the tutelage of Naomi, Viney and Uncle Abram, Jason becomes attuned to life as a slave. One day, when Jason is sent to the retrieve something in the smokehouse, he is frightened by several African tribesmen. Fearful that they are cannibals, Jason runs away, but is later told that they are the Songhais. Although the importation of slaves has been illegal for decades, the Songhais have been brought to America because they are unusually good with horses. Jason soon befriends the Songhais and tries to talk them into escaping with him to Mexico, which is less than one hundred and fifty miles away. They do not understand him, but when Jason starts to talk gibberish that sounds as if it could be African, they respond by bowing, as if he were their chief. Soon, Quincy and Ginger arrive at the Calloway plantation posing as missionaries looking for the disease-carrying slave. Quincy, overjoyed finally to find Jason, insists on isolating him, while at the same time receiving $500 from Calloway for a serum that purportedly will save his family from a terrible death. When Quincy and Jason are alone, they embrace and laugh, but instead of leaving immediately, Jason insists that they take along all of the other Calloway slaves. Although irritated over Jason's ultimatum, Quincy agrees, and that night makes a plan with Ginger whereby she will leave first and arrange for fresh horses on the trail. The next day, after Ginger has left, Plunkett rides onto the plantation and tells Calloway the truth about Ginger and Quincy. Calloway and Plunkett then go after Jason and Quincy, who are saved by the Songhais, who respond to Jason’s commands. After a scuffle, Plunkett is about to shoot Quincy when Jason shoots and kills him instead. Now Jason, Naomi, the Songhais and slaves Viney, Ned and Uncle Abram, climb into the family carriage and race away alongside Quincy. Soon they arrive at an abandoned building where Ginger was to have left fresh horses. At first they think that she has taken the money for herself, but soon see the horses and continue on to Mexico. In a small border town, Ginger happily greets everyone, and they have a celebration that night. Although Quincy talks to Jason about heading west to start a new game in the gold rush area, Jason is reticent about leaving the others and says that he will join Quincy later. Quincy says that they are like brothers, but Jason points out that they are different because he can be bought and sold. The next day, Ginger and Quincy are riding on the range, when Quincy reveals that Jason stole their $3,000 stake in the middle of the night. Ginger is shocked that Quincy watched Jason steal the money and did nothing, but Quincy assures her that it is fine because he has the bankbook for their Chicago account that contains $10,000 of their money. Ginger holds up the bankbook and says that she has always found that the best way to hold a man is to get a firm grip on his bankbook, then gallops ahead, with Quincy in pursuit, saying that he loves her.