Arizona 1885 – Cavalry Captain Case McCloud (George Montgomery) tries to maintain the treaty between the Apache led by Geronimo (Miguel Inclan – who had previously played Cochise in John Ford's Fort Apache) and the government that keeps white prospectors off Apache territory. But local Tucson businessmen, including Cliff Taggert, stir up trouble and when a new cavalry commander Maj. Nathan Stark (Robert Shayne) arrives, he recalls his troops and allows local prospectors back to their mines. McCloud does everything in his power to stop all-out war.
Taggert has an old miner, Sagebrush (Eddie Waller), killed and pretends that the Apaches did it. McCloud does detective work and proves that the arrow that hit the miner was from another tribe than the Apaches. Nevertheless, Stark captures Geronimo and refuses to follow a treaty. Geronimo will be sent to prison in Florida, but when Case decides to resign from the Army in protest, Geronimo tells Case that Case's sword is honorable, as he fought for the Apaches' rights. Case remains in the Army and marries his schoolteacher girlfriend Norma Clemson (Audrey Long), who runs a school for the Apaches.