Two boys from different cultures, one a Texan, one a New Mexican, get caught on opposite sides of the U.S. Civil War. Jemmy Martin wants to stay on the family farm near San Antonio, Texas. When his brother becomes a packer for a regiment of Texas Mounted Volunteers, then deserts, Jemmy takes his brother's identity to protect him from the firing squad. Now all Jemmy wants is to get himself and his family mules back to the farm where they belong...