Jim Harvey (Western legend Audie Murphy, Gunsmoke) is a guard on a westbound wagon train, ready for action. After saving the life of a Yaqui Indian warrior named Tigre (Eugene Iglesias), the wagon train is subject to a surprise attack. With lives on the line, Harvey realises that their only chance of survival is to negotiate a truce with Tigre's father - chief Aguila (Ralph Moody). But between trust and deceit echoes the cry of loyalty - and through a chilling twist of fate Harvey falls victim to his own idealism - taken prisoner by the warring natives and branded a deserter by his colleagues. Tormented by the past, with his reputation in tatters, Harvey is man ready to risk it all and clear his name for good.