Teenage Zombies - Don Sullivan, Katherine Victor, Steve Conte and J.L.D. Morrison. Directed by Jerry Warren (1960)

SCI FI TV

While boating (and possibly water-skiing), a quartet of teens, Reg (Don Sullivan), Skip (Paul Pepper), Julie (Mitzie Albertson), and Pam (Brianne Murphy), accidentally discover an island run by a mad scientist named Doctor Myra who, backed by foreign agents from "the East", intends to turn everyone in the United States into a zombie

https://en.wikipedia.org/wiki/Teenage_Zombies

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