Following in his dad's footsteps, Shefford devotes himself to freeing his community from the grip of a particularly despotic Mormon sect. In so doing, he rescues his foster sister Fay Larkin, who is coveted by lecherous Mormon elder Wagoner. As was the case in Riders of the Purple Sage, the Mormons are villains simply because they are Mormons.
True Blue begins with the marriage of black-sheep British nobleman Gilbert Brockhurst to the daughter of a Western rancher. When he learns that he has inherited his father's title and estate, Brockhurst deserts his wife and young son Bob. Upon attaining adulthood, Bob becomes the boss of his grandfather's ranch.