The early 1970's produced some terrible horror films and this is one of them. The Bat People is simply god-awful. The story begins when a doctor is bitten by a bat while on vacation with his wife. He then begins his metamorphosis into a literal bat man. I can hear you groaning as you read this. The pace of the film is slightly slower than death. Every scene that's meant to instill terror in the viewer produced in me rolls of laughter. Nothing scary here. But as an unintentional comedy, it's pretty darn funny in a number of places.
It's pointless to talk about the actors, none of whom you've ever heard of. Or the soundtrack which is soooooo bad. Or the special effects which are, as I've stated above, most likely to induce laughter. Just put this one in a cave with the bats and make sure you seal it tight!! For the love of things vampire, please watch something else.
For more info check out the film's entry in IMDB.