Delmar Spavinaw, an educated "half-breed," loves Evelyn Huntington, daughter of a racist judge. Evelyn's other suitor is Ross Kennion, a widower with one child, and owner of a vast tract of land which Spavinaw insists belongs to his Indian mother. Spavinaw seeks revenge when Judge Huntington decides to evict the squaw. Assisted by Juan Del Rey, a cattle rustler, Spavinaw steals the title to the land, wounds Kennion, stages a raid on the judge's cattle, and attempts to kidnap Kennion's son and Evelyn. The arrival of the sheriff forces him into flight across the border without his hostages. En route he meets Doll Pardeau, a school friend of Evelyn's, and together they ride for the Mexican border. Caught between a cattle stampede and a sheriff's posse, the couple catch a passing freight train, leaving calamity behind as the train slowly passes.

During World War I, a professional thief known as The Lone Wolf is assigned to steal a cylinder with important information from behind the German lines and bring it to Allied intelligence headquarters. However, German agents set out to stop him, headed by the man who was responsible for the death of the thief's sister.