Rewarded for his heroism in the Civil War, Lt. John Dunbar (Kevin Costner) wants to see the American frontier before it is gone. He is assigned to an abandoned fort, where a Sioux tribes is his only neighbor. Overcoming the language barrier and their mutual fear and distrust, Dunbar and the proud Indians gradually become friends. Eventually he falls in love with the beautiful "Stands With A Fist" (Mary McDonnell), a white woman raised by the tribe. He learns the culture of the Sioux, lives with them, and even experiences the heartbreaking excitement of a buffalo hunt, but his knowledge of the fate which will ultimately befall the tribe haunts him. Finally he is faced with a crucial decision that will cause him to examine his heart and soul before making a heroic that determines his desitny.