Trappers with government support force the Yellow Hands Sioux off their sacred land. The Indians retreat, but await supernatural punishment to descend on their usurpers. John Morgan, 8th Earl of Kildare, who had lived with the tribe for years and is known as Horse, leaves his English fiancée and estate and returns to America, where he discovers the Yellow Hand people have been largely massacred or put into slavery by the unscrupulous white traders and their Indian cohorts. The few survivors, including wise old Running Bull and stubborn old Elk Woman (Gale Sondergaard) have gone into the Badlands and been forced to eat their dogs. "Why did you return?" asks Elk Woman. "I had to come back," says Morgan. "I had to prove something to myself... there was an empty place in my soul. I could not forget." He finds the tribe dispirited, because of the actions of the trappers, and he begins to devise a strategy to overpower the trappers' stronghold, convincing the Indians to take direct action. Soon even the Indian women and boys are assigned tasks to aid the assault to regain their ancestral land.