Lt. Col. Kirby Yorke is posted on the Texas frontier to defend settlers against depredations of marauding Apaches. Col. Yorke is under considerable stress by a serious shortage of troops of his command. Tension is added when Yorke's son (whom he hasn't seen in fifteen years), Trooper Jeff Yorke, is one of 18 recruits sent to the regiment.

John Wayneas Lt. Col. Kirby Yorke
Maureen O'Haraas Mrs. Kathleen Yorke
Ben Johnsonas Trooper Travis Tyree
Claude Jarman Jr.as Trooper Jefferson 'Jeff' Yorke
Harry Carey Jr.as Trooper Daniel 'Sandy' Boone
Chill Willsas Dr. Wilkins
J. Carrol Naishas Lt. Gen. Philip Sheridan
Victor McLaglenas Sgt. Maj. Timothy Quincannon
Grant Withersas U.S. Deputy Marshal
Bert Glennon