Beach Blanket Bloodbath(1985)

Bibi is being held captive by three mad scientists, the leader of whom is her own sister. Bibi's sister plans to remove half of Bibi's brain, an operation Bibi thinks will be obvious to her friends at school. The scientists are not so sure. Finally, Surfer Bob and a butch biker chick rescue Bibi and make their escape. Segment from Sleazemania Strikes Back.