An arrogant officer refuses to let his daughter marry a lieutenant, fails to make peace, and leads his men into an unnecessary Apache ambush.
Lt. Col. Owen Thursday (Henry Fonda) and his daughter Philadelphia Thursday (Shirley Temple) arrive at Fort Apache with Lt. Michael Shannon O'Rourke (John Agar) during a dance. Lt. O'Rourke is welcomed by his father Sergeant Major Michael O'Rourke (Ward Bond) and mother Mary O'Rourke (Irene Rich).
Lt. O'Rourke presents his card to Philadelphia. Col. Thursday takes command and reprimands the dress of the officers. Captain Kirby York (John Wayne) has more respect for the Apaches. Philadelphia gets help from Emily Collingwood (Anna Lee) and Mary O'Rourke in fixing up Thursday's home. Lt. O'Rourke is drilling new men, but his father lets Sergeant Festus Mulcahy (Victor McLaglen) take over. Philadelphia goes to a party for Lt. O'Rourke.
Sergeant Beaufort (Pedro Armendariz) teaches the new men to ride horses without saddles, and they fall off. Philadelphia goes riding with Lt. O'Rourke. Thursday learns the Apaches are coming south and that Lt. O'Rourke is out with Philadelphia. Lt. O'Rourke reports two dead. Thursday reprimands him and forbids him to see Philadelphia. Thursday sends Lt. O'Rourke with four men to repair the wire. Thursday and York lead out the troops. Lt. O'Rourke is ambushed by Apaches. Thursday's men go to the store of Silas Meacham (Grant Withers). York accuses him of selling liquor to the Apaches and says that made Cochise leave for Mexico. Thursday finds cheap whiskey and orders it destroyed. Mulcahy and his men get drunk and are punished.
York tells Thursday that Cochise trusts him. York leaves with Beaufort, and they go to Mexico. Philadelphia visits the O'Rourkes. Thursday comes to get her, and Lt. O'Rourke asks Philadelphia to marry him. She says yes, but Thursday says she is not of legal age. York and Beaufort meet with Cochise. Officers are dancing when they return. York tells Thursday that Cochise is coming to talk peace, but Thursday orders the men to march. York objects that his promise will be broken.
Thursday leads out the singing troops. Emily learns her husband got a transfer, but she does not call him back. York suspects an Apache ambush and tells Thursday the Apaches outnumber them four to one. Thursday talks with Cochise, who says he wants peace but insists that Meacham must go. Thursday orders Cochise to return to the reservation, or they will attack. York advises against it, but Thursday orders a charge and calls York a coward. York challenges Thursday and is ordered to stay behind with Lt. O'Rourke. Thursday leads the charge into the ambush. Thursday is down, and men fight on the ground. York has wagons turned over and sends Lt. O'Rourke to Fort Grant for help. York finds Thursday and gives him his horse, but Thursday takes his saber and goes back into the fight. The Apaches charge and wipe out Thursday's men. Unarmed York meets Cochise, and the Apaches leave.
In the final scene York tells reporters that the campaign against Geronimo will be long. They consider Thursday a hero, and York says the dead live in the regiment. Philadelphia has married Lt. O'Rourke, and York leads the troops.
This drama is similar to the Sioux massacres led by
Crazy Horse against Captain Fetterman in 1866 and General Custer
ten years later, but it is adapted to the peace-loving Apache
chief Cochise, who was mistreated, allowing Geronimo to rise up.
The folly of an overly ambitious commander is exposed.