Calamity Jane and Sam Bass, starring Yvonne de Carlo and Howard Duff, is a rousing tale of a gifted horseman torn between two women. When Sam Bass (Duff) arrives in Denton, Texas, he immediately earns the suspicion of the Sheriff and the admiration of his kind-hearted sister, Katherine (Dorothy Hart). Sam, in turn, has caught the eye of the famed Calamity Jane (De Carlo), who is impressed by his winning techniques with her prized horse Thunderbolt. Sam's fortunes seem to be on the rise when he makes a large sum of money in a race, but his horse and his hearts desire are jeopardized when he becomes involved with a notorious team of outlaws.