An alliance between two longtime friends is in danger when a mutual enemy comes into possession of a damning secret. Setting: Chihuahua, Mexico. After a Prologue in 1905, the action moves forward to 1915.Although they have many similarities, Mexico's singing westerns tend to be far more realistic and more "adult" than their Hollywood counterparts. This one is not only loaded with musical numbers (one of which even lauds the differences between Texan cowboys and their "Northerner" neighbors), yet introduces a highly suspenseful action plot line that censors would never allow across the border (even though handled with great sensitivity).The movie showcases Pedro Infante, who acts the role of the tarnished hero as ingratiatingly as the way he handles a song. The support cast is likewise excellent, with a special mention for Mendoza as the troubled friend, Perez as the stop-at-nothing villain (although one can't help feeling a bit sorry for him), and Alfonso Bedolla as the Yaqui.