In the fourth of the highly successful Frankie and Annette beach party movies, a motorcycle gang led by Eric Von Zipper kidnaps singing star Sugar Kane managed by Bullets, who hires sky-diving surfers Steve and Bonnie from Big Drop for a publicity stunt. With the usual gang of kids and a mermaid named Lorelei.
A Martian teenager sent to prepare for an invasion falls in love with an Earth girl.
Local beach-goers find that their beach has been taken over by a businessman training a stable of body builders.
