Jim awakens to find that his already gigantic head has grown even larger -- so large, in fact, that it's wedged in the four corners of his bedroom ceiling. A visit from Dr. Axel results in the draining of a green ooze from Jim's brain and a prescription for a stress free vacation. Jim, Roy, Ivan, Ray and Dr. Axel head out on a fishing trip to find the legendary giant blue fish. Shortly after their departure on the water, the gas tank gets punctured and the boat explodes, leaving them stranded on a remote island. Soon Axel and Ivan are kidnapped by an evil old man who breeds the blue fish... and they discover that the fish live off of human flesh.