WEIRD! GHOULISH ATOMIC BEASTS WHO LIVE OFF HUMAN BLOOD!
Radioactive waste dumped off the coastline creates mutant monsters. The beasts attack slumber parties, beaches, tourists, and terrorize a waterfront community as a scientist, his daughter, her boyfriend and the local police try to find a way to stop them.
Is this the one where a significant portion of the movie is dancing?
If so, this movie is a gem
Though I recall it being in colour? Maybe that’s my imagination.
There are a few dancing scenes, but I wouldn’t say that it’s a significant portion of the movie. Maybe you’re thinking of a different beach-party monster movie?
The trailer says “The first horror-monster musical” so maybe…