A film series about the roving cowboy adventurer starring Ty Hardin.

A U.S. Army major is sent on a perilous mission to recover army money stolen by the chief of the Sioux Indians, Sitting Bull. Bronco agrees to act as his guide and they are joined by the only survivor from an ambush by the Sioux. As the three travel further into dangerous Indian territory, Bronco begins to suspect that Sitting Bull is not the only enemy.