Kirrin Cottage is bursting with people and Uncle Quentin can't take it anymore. Therefore, the Five, Tinker and his monkey, are sent off to live in Tinker's lighthouse at Demon's Rocks. Many tales exist about the treasures hidden in the caves by Wreckers of yore. Mischief, the monkey, discovers a gold coin upon their visit to the caves. The news spreads and tensions rise. Who will find the treasure first?