Max isn't as good a detective as he thinks. His son Sam's a better sleuth. Together with his tomboy neighbor and a rich baron's son, Sam helps Max search for a stolen rare parrot. When a band of criminals kidnaps Max, the kids tail them in a speedboat and strand on a remote island fort. Something's being hidden there... As they unravel the mystery, they're pursued by a creepy villain who guards the fort day and night.—Holland Film