When his best friend moves away, eleven-year-old Layton Clark wonders if he'll ever have another adventure. Then he meets Sherry. She introduces him to the treasure-hunting world of geocaching. A contagious thirst for adventure sends them hunting for mysterious geocaches popping up in random places-like an abandoned Kansas ghost town.

Layton and Sherry must work together to unlock the clues in the strange geocaches, solve a 100 year old mystery to clear a dead man's name, and convince Layton's archaeologist father the town is worth studying further so his family doesn't have to move.

With everything he holds dear at stake, Layton can't afford to leave a single headstone unscrubbed, or geocache treasure undiscovered.