Off the coast of Florida, a nearly-deserted island is rumored to have the fountain of youth. A boatload of teenage kids are headed there for a scavenger hunt. Wellington, the island's wealthy owner, is none too happy about that, so he dispatches his daughter, Junior, to get rid of them. She's happy to go because her sweetie, Irving, is the island's only resident. Junior sends Irving to spy on the kids to find out what they know. Irving's twin brother, Herman, and Herman's high-school sweetheart, Camille Salamander, are also headed for the island with their own nefarious plans. Is the fountain of youth real, and if so, who will get to it first?
On a small island near Florida, a dozen teenagers combine singing and dancing on the beach with a search for buried treasure. They do not know that Irving, "The Fat Spy," is also there seeking Ponce de León's legendary Fountain of Youth for cosmetics tycoon Wellington. When Irving fails to drive the youngsters from the island, he calls upon his brother Herman for help. Herman is madly in love with another cosmetics manufacturer, Camille, who is also searching for the precious youth fluid. And completing the group of modern-day explorers is Wellington's seductive daughter, Junior. After a series of mishaps and mixups, all concerned finally descend upon the fountain. But they are thwarted by the sudden and miraculous appearance of Ponce de León and his fiancée, who prevent their treasured secret from falling into the hands of mere mortals.
