When a bear injures Trapper Lije Hawks, his nephew Yancey, who has never been out of the mountains before, must go to the city of Casper to sell their beaver pelts. On his way to Casper Yancey is joined by Rosalie, a dowdy young girl fleeing her father, who tried to trade her for Yancey's pelts. Yancey does not want to take her with him, but she looks at him so imploringly that he gets angry but defenseless. Rosalie says that she wants to get a job in Casper, but really she is deeply impressed by Yancey.
Yancey and Rosalie arrive in Casper on the 4th of July. They are at once noticed for their shabby look. Cowboy Chip and his pals make fun of them, and soon Yancey finds himself involved in a serious fight.
Ma Ransom offers Rosalie a job at the dancehall. Rosalie does not want to take that job, but Yancey is happy to get rid of her, because he wants to meet Marcy Howard again. Rosalie soon finds herself escorted by the Sheriff, who is in fact the owner of the dance hall. The decent citizens would like to close that place, but the Sheriff is the fastest gun in town and nobody dares to start a fight with him. He makes Ma Ransom dress Rosalie up bewitchingly for a very private dinner with himself.
Meanwhile Yancey manages to get friendly with Marcy Howard, who has a day off. He treats her like a true lady, which she enjoys very much for a change. She teaches him how to dance, but when they join a public dance, the dance floor empties quickly. After another fight with Chip, Yancey learns what kind of a woman Marcy is. Yancey realizes what job he made Rosalie accept and rushes to the dance hall to rescue her. He gets thrown out and beaten up, but when he returns with his gun and Sheriff Paul Bartell still would not set Rosalie free, Yancey kills him in a duel.
The citizens are happy to be freed of their evil Sheriff, and the Forbes offer Rosalie a job at the General Store, but when Yancey tries to say goodbye to her, she looks at him again, and of course Yancey cannot resist that look.They ride off together on horseback.