Ludzie-nietoperze was released in the year 1974。Ludzie-nietoperze is also called as The Bat People, Morso del pipistrello, It's Alive, It Lives by Night, Bat People - Die Blutsauger, Angel of Fear。

A doctor specializing in bats, and his new wife interrupt their honeymoon to go spelunking in Carlsbad Cavern. There he is bitten by a fruit bat and inexplicably undergoes a transformation into a vampire bat. He ultimately escapes, however, escaping back to the caves. His wife, infected by her husband, kills the local constabulary and goes to join him.