The Incredibly Strange Creatures Who Stopped Living and Became Mixed-Up Zombies (sometimes "!!?" is appended to the title and shortened to The Incredibly Strange Creatures) is a 1964 American monster movie produced and directed by Ray Dennis Steckler. Steckler also starred in the film, billed under the pseudonym "Cash Flagg".

In the film, three friends visit a carnival and stumble onto a group of occultists and disfigured monsters. Produced on a $38,000 budget, much of it takes place at The Pike amusement park in Long Beach, California, which resembles Brooklyn's Coney Island. The film was billed as the first "monster musical," beating out The Horror of Party Beach by a mere month in release date.

Upon release, the film received negative reviews and is regarded by some critics as being one of the worst movies ever made. The film was lampooned in a 1997 episode of the cult sci-fi TV series Mystery Science Theater 3000.