At the turn of the century, Denny O'Moore Mickey Rooney), is en route from his New York City home to Texas, to pay his brother Patrick (Robert Stack) a surprise visit at the latter's silver mine across the Mexico border. Denny meets Texas Ranger Joe Waldner (Robert Preston), who suspects that Patrick is involved with the notorious Mexican bandit El Tigre. Denny and Waldner are captured by El Tigre's henchmen but escape. Denny appeals to Carmel Alvarado (Wanda Hendrix), Patrick's sweetheart, to try and talk Patrick into leaving El Tigre, and falls in love with her himself. The bandits, headed by the mysterious El Tigre, surround Denny, Waldner, and Carmen in an old hacienda in Mexico.