A Virginia farmer during the Civil War refuses to support either the Confederacy or the Union until his son is taken prisoner and, seeing the horrors of war first-hand, he is forced at last to take his stand.

A plains drifter cowboy single-handedly rescues a local nun from a gang of attackers. After meeting a band of Mexican revolutionaries, who are resisting the French occupation of Mexico, the cowboy and Sister Sara decide to join forces with the freedom fighters and set off on a deadly mission to capture the enemy's garrison. But along the way the soft-spoken hero discovers that the nun is not what she seems.