Teenagers from a small town and their high school science teacher join forces to battle a giant mutant spider, living in a cave nearby and getting hungry.
Glenn Manning, "The Amazing Colossal Man," believed dead after falling from the Hoover Dam, reemerges in rural Mexico, brain damaged, disfigured, and very angry.
A deranged scientist creates a ray that can shrink people down to doll size.
An evil alien brain, bent on world domination, takes over the body of an atomic scientist, while a "good" alien brain inhabits the body of the scientist's dog and waits for an opportunity to defeat the evil brain.