Red Mountain

In Colorado, 1865, a gold assayer is killed and Lane Waldron is seen leaving the scene. A posse chases him and a lynch mob forms around Lane, threatening to string him up. At the last moment, a noose around Lane's neck is shot in half by an unseen marksman, sparing his life.

The unseen marksman is revealed to be Brett Sherwood, a Confederate captain. He intervenes to save Lane from the mob, and the two flee to safety at a cabin Lane knows.

Lane and Brett escape to a cabin that Lane knows well and shelter there. Brett tests Lane by leaving a gun unattended, and Lane grabs it only to discover that it is not loaded. Brett then ties Lane up and leaves him to guard himself.

Lane's sweetheart Chris arrives at the cabin and releases Lane from his bonds. Lane and Chris then trail Brett, determined to capture him, turning the pursuit into a joint effort.

The trio takes turns guarding Brett through the night. Chris and Brett discuss the Civil War, and Chris reveals her loyalties diverge from Lane, expressing hatred for Quantrill and the killers who ravaged her family.

As Brett prepares to escape, a struggle breaks out and Lane suffers a broken leg. Brett halts his own escape to stay and help Lane, showing a fragile alliance between them.

Brett and Chris locate a cave and manage to get Lane inside for safety. While Brett goes to fetch a doctor, Quantrill and his raiders arrive and capture Lane and Chris.

Quantrill has set up an ambush for the US Army. One of Quantrill's men tries to assault Chris, but she shoots him, warning the army of the ambush.

Quantrill learns of Lane's gold mine and decides to keep him alive. He sends Chris and Randall to town for a doctor, while Brett begins to question Quantrill's motives.

Brett and Chris return with a doctor who operates on Lane, saving his life and his leg. The operation buys Lane time, but Quantrill's grip on the captives remains precarious.

Quantrill decides to kill the captives anyway. Brett brings food and guns and helps the doctor escape so he can get help. The doctor is captured and killed, and Brett slips away to seek assistance.

A band of Indians who had been working with Quantrill attack Chris and Lane at the cave. Lane is shot by a Ute and, though Chris kills the assailant, Lane lies dying. Before dying, Lane asks that Chris and Brett inherit his gold mine.

Brett arrives with the Army and posse, pursues Quantrill, and kills him in the confrontation. He also reveals that he was the one who killed the assayer who had tried to cheat him, tying the event to the earlier murder.