The mysterious Don Del Oro ("Lord of Gold"), an idol of the Yaqui Indians, has emerged and attacks the gold trade of the Republic of Mexico, with plans to take over the land and become Emperor. A man named Francisco was put in charge of a fighting legion to combat the Yaqui tribe and protect the gold, but he was attacked by a few men working under Don Del Oro. Zorro came to his rescue but it was too late for him. Francisco's partner recognized Zorro as the hidalgo Don Diego Vega. Francisco asked Diego to take over the fighting legion as his alter-ego Zorro and defeat Don Del Oro.