Bobby Benson's B-Bar-B Riders #4

Bobby Benson and Miss "Lemonade" Brayne must stop the Spider—a criminal mastermind operating from Mexico who has kidnapped wealthy Mexicans and is using a deadly mechanical saw to execute his victims. The story involves Bobby's pursuit across the Mexican border, encounters with the Spider's agents, a dangerous saw-trap at a lumber mill, and ultimately Bobby's battle to rescue the captives and capture the Spider before he can complete his deadly plan.