The Hardy boys come to the Yucatan to take on a gang of grave robbers. Stolen Mexican artifacts have appeared in Bayport, and Frank and Joe intend to cut the smugglers off at the source. But the jungle is full of deception and distraction, including a bevy of beautiful models who have appeared at the site for a photography shoot.

A different kind of shooting, though, quickly puts the Hardys back on track. The raiders of the Mayan pyramids are packing automatic weapons, and they're not about to give up their lucrative looting without a fight. They plan to draw Frank and Joe into the jungle and add two deep new chambers to the ancient tombs!