While Nancy and her friends from River Heights are enjoying spring vacation in Fort Lauderdale, Florida, the young detective is approached by wealthy elderly woman who asks hor her help. Her house has been burglarized frequently, but the would-be thieves only ransack the home- nothing is ever taken! As Nancy sets off to find the culprits, she must also take on another assignment. An international ring of stamp forgers and smugglers are discovered in Southern Florida and Nancy must find a way to stop them. Almost swallowed by one of frightening "sink doles" of Florida, the young detective persists in her quest for a solution along Ocean Boulevard!