The film begins at a board of inquiry over the Battle of the Little Big Horn, specifically examining the conduct of Major Marcus Reno.

Captain Bill Benton (perhaps inspired by Frederick Benteen) is called to the stand, and rather than merely answer questions from the board, states that he will tell his version of the "true story" that the audience sees through flashback.

Benton's army scout "Dakota" advises against tracking the Indians until the next day due to their laying of false trails that lead into ambushes.

Custer invites Benton to a dress dance held at the fort that evening and dismisses the distraught Mr. Turner by telling him that he will visit the hostile Indians who abducted his wife in the morning.

Meanwhile, back in the West, the Army's commander General Alfred Howe Terry visits the fort and summons Major Reno and Captain Benton to inform them that Custer is going to be court-martialed.

In Washington, DC, Senator James G. Blaine visits the humbled Custer and tempts him with an offer to be his party's candidate for President of the United States.

Benton notices that Custer's empathetic feelings for the Native Americans have vanished and he is pushing his regiment into a war where he can claim glory.

The screenplay by Salkow and Marvin Gluck was credited as "Fred C. Dobbs", the name of Humphrey Bogart's character in The Treasure of the Sierra Madre (1948) and then the name of a nightclub on Sunset Strip.