One day Pete and Pam Hollister rescued a Seminole Indian named Charlie Tiger Tail from drowning in Pine Lake. But they never dreamed that their heroic act would lead to a new, exciting mystery and a vacation in Florida. Within a few days, all the Hollisters were enjoying the beach at Turtle Point in the Everglades. And they were eager to help Charlie catch a gang of thieves who were illegally killing giant sea turtles and stealing their eggs! After Holly found a poacher's spear, Ricky and Pete patrolled the beach one night and almost trapped the poachers. With Charlie's ten-year-old daughter, Clementine, the children rowed to mysterious Captive Island to investigate the eerie sounds coming from there each night. They inspected a great Mississippi riverboat that had been towed up on land and turned into a huge mansion. And they visited Clementine's grandmother in a Seminole village where the boys learned how to pole a real dugout canoe. There were many more thrilling adventures-including Ricky's capture by the thieves-before the Hollisters finally traced the poachers to their hideout and solved the sea turtle mystery.