The San Diego mission- guarded by the moody Father Xavier – hides the proof of ancient technologies and alien landings. And while El Morisco studies the part of the Aztec codex that has been found, the Jaguar men attack! When the clashes are over, one of Montales’ soldiers recognizes one of his cousins from Valle de Rosario in the body of one of the monsters. Our heroes thus follow the new trail, after having witnessed the folly of Father Xavier, who blows up the mission with all of his secrets! Having arrived at their destination, Tex and the others find an ally in Antonio Herrera, owner of the surrounding mines.