A U.S. Army soldier is allowed to pick his post; he decides to see the West before it is settled. Sent to protect a U.S. outpost on the desolate frontier, Lt. John Dunbar finds himself alone in the vast wilderness. Befriending the very people he's sent to protect the outpost from, the Sioux Indians, Dunbar slowly comes to revere those he once feared. When the encroaching U.S. Army threatens to overrun the Sioux, he is forced to make a difficult choice.