John Wayne, Rock Hudson, Lee Meriwether and Merlin Olson star! Two Colonels—one from the Union and one from the Confederacy—must work together despite their differences as they travel towards Mexico. Along the way, they fight off both bandits and revolutionaries as they fight to lead their loved ones to safety.
Union Colonel John Henry Thomas doesn’t know that the Civil War has come to an end when he carries out one last attack. After his blood-soaked victory, Thomas learns that the war ended just three days earlier at Appomattox. Bone-weary and tired, Thomas gathers his men and leads them out West to earn some money selling horses. Along the way, Thomas meets up with his adopted son, Blue Boy, and other members of the Cherokee tribe.

At the same time, a band of Confederate soldiers led by Colonel James Langdon decide to leave America. Fearing that the War has left them with nothing to return to, Langdon gathers his family and friends and heads to Mexico to serve Emperor Maximilian, leader of the French intervention in Mexico, and the enemy of President Benito Juarez.

The two groups meet when Blue Boy and Thomas discover that Mexican Commanchero bandits are planning an ambush on the Confederate soldiers. Although they still have their differences, these Americans—Union, Confederate, and Cherokees—unite to defeat the banditos. They celebrate with a “Fourth of July” party that ends in a drunken brawl…and results in a pair of star-crossed lovers: Thomas’ son, Blue Boy…and Langdon’s daughter, Charlotte.

After the fight, the two groups split up. But when the Confederates arrive in Durango, they are taken hostage by Juarez supporters, who make a hefty ransom demand. Now, the Union soldiers vow to free their fellow Americans…as long as they can get there alive!