When a group of Mormons are run out of town for their religious beliefs, Elder Wiggs (Ward Bond) searches for a wagon master to guide the outcasts to the San Juan Valley. Happening upon horse traders Travis Blue (Ben Johnson) and Sandy (Harry Carey Jr.), Wiggs convinces the men to take the position due to their intimate knowledge of the area. Despite Blue and Sandy's guidance, the travelers experience numerous setbacks, especially when the Clegg family outlaws take refuge in their wagon train.