The Ricks', in need of some TLC, take off to a nearby island to go camping. On their way they get word that there is an escaped convict at large. Porter gets permission to continue on his vacation, but after his boat is stolen, he gets a feeling that this is no vacation. Flipper takes off in hot pursuit!

In the conclusion of a two-part adventure, Flipper tows Porter Ricks to his stolen launch, where he finds that the thief has imprisoned Ulla and stolen her submarine.