William Munny is a retired, once-ruthless killer turned gentle widower and hog farmer. To help support his two motherless children, he accepts one last bounty-hunter mission to find the men who brutalized a prostitute. Joined by his former partner and a cocky greenhorn, he takes on a corrupt sheriff.

As a Civil War veteran spends years searching for a young niece captured by Indians, his motivation becomes increasingly questionable.

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