She Devil (1957)

Starring Mari Blanchard, Jack Kelly, Albert Dekker, John Archer, Fay Baker
Directed by Kurt Neumann
(actor & director credits courtesy IMDB.com)

A scientist injects a dying woman with an experimental serum, and she completely recovers, but also gains strange abilities and loses her inhibitions, transforming her into a predatory female.

This film has a fascinating hook- what if we applied the ability of insects to adapt and heal themselves to human beings, and what abilities could they develop?  Although we get to see these abilities manifest themselves in Blanchard's character, it's not really what the film's about, instead turning into a monster movie with a liberated woman as the creature.  Whether the filmmakers are using this as a vehicle to say something about repression or sexism in the '50's, or trying to reinforce such attitudes, I don't know, but the results are an entertaining romp, although one that can't be taken seriously in the slightest.  It's a hoot though, and Blanchard makes a fine villainess.  Director Neumann's better known for his follow-up the next year, The Fly, but once you see its predecessor, you won't be able to forget it.