While the Civil War rages on between the Union and the Confederacy, three men – a quiet loner, a ruthless hitman, and a Mexican bandit – comb the American Southwest in search of a strongbox containing $200,000 in stolen gold.

Two bounty hunters both pursue a brutal and sadistic bandit El Indio who has a massive bounty on his head.

Wounded Civil War soldier John Dunbar tries to commit suicide—and becomes a hero instead. As a reward, he's assigned to his dream post, a remote junction on the Western frontier, and soon makes unlikely friends with the local Sioux tribe.