When Molly Collins and the Detective Club discover a chest of gold, a treasure map is found among the coins. The children are excited and eager to hunt down the treasure, but how can they when the parchment is suddenly stolen? Molly and her brother John, along with the club, track down clues as they try to figure out where to go next. Who will reach the treasure first? The children? Or the thief? Join the club on another exciting adventure as they race against time to figure out the secret of Laketown.