En route to the upper westernDakota Territory (now North Dakota), where Vickers plans to reenlist in the Army as a buck private recruit, then join the men under the command of General George Armstrong Custer (1839-1876), (James Millican), at Fort Abraham Lincoln, to continue his search in the ranks of the Army cavalry, he sees a sergeant named O'Hara (Forrest Tucker) physically manhandling an attractive young woman. Molly Quade (Polly Bergen), is grateful for his intervention, but Sgt. O'Hara gets even later when Vickers coincidentally ends up serving under him at the fort, giving him the most unpleasant menial dirty duties and assignments.
Molly has come to the fort to help her father Sam Quade (Dean Jagger), run a general store. He is opposed to her attraction to this new recruit Vickers. While out on an assigned mission, a troop of soldiers led by Captain Gregson (Harry Carey Jr.), are badly outnumbered by a band of LakotaSioux warriors until being rescued by General Custer and his troops. Vickers is recognized by General Custer as a former Union Army officer from his Civil War days a decade before and is promoted to first sergeant.
O'Hara realizes that Vickers suspects him to be one of the killers of his fiancée. An ambush attempt fails, so the Sergeant deserts the Army and flees. A military wagon train is formed to evacuate civilians from the fort while Custer prepares to do battle with the Sioux natives near the Little Bighorn River further west in the southeastern portion of the adjacent Montana Territory at what turns out to be the later tragedy of the famous Battle of the Little Bighorn in June 1876, but along the way, Molly, her father and now Sgt. Vickers and several others are taken captive. They see that ex-Sgt. O'Hara is a prisoner too, and when he learns Custer's troops of men will be hopelessly outnumbered and trapped on two sides of separate bands of thousands of warriors and probably slaughtered, despite his earlier crimes and desertion, he tries to go warn the general and sacrifices his own life running through a gauntlet line in the village, distracting the Sioux until the others led by Vickers can escape.
After Molly and her father Sam with Vickers grab some unguarded horses behind their tent and rideM off , then a distance further off, hide from the Indians until daylight. Molly becomes aware that her father, turns out to be the third killer that Sgt. Vickers has been seeking for years. Before she can persuade Vickers not to kill him, Sam Quade rides off in the darkness by himself to try to warn Custer, which will certainly lead to his own death.
^THOMAS F. BRADY (August 5, 1950). "ROLE IN WAR PATH' TO EDMOND O'BRIEN: Actor Signed for Paramount Picture Based on Novel by Gruber--Haskin to Direct". New York Times. p. 9.
