Loco Luke was a prospector working an area of old Spanish mines left over from the age of the era of the Conquistadors. Stew Carey and Strong Bow discover his body while searching for Jigg Larsen. Jigg and his gang of cattle rustlers stole cattle from the Rancho Oro, set the ranch house on fire with Stew inside, and kidnapped Laura Towne. At first, Stew recognizes the prostrate form of Loco Luke laying by the prospector's mule, thinking the prospector had fallen from the pack animal. On closer inspection, Stew surmises that Jigg's band of renegades shot Loco Luke to death.