The Snake Woman (1961)

"Weird! Supernatural! Horrifying! Serpent-Girl Terrorizes Town! Teen-age beauty turns into deadly reptile at will...spreading horror with fang and forked tongue! Nothing ever struck you like The Snake Woman!"

A doctor in 1890 England, in order to cure his wife's "sick mind," injects her with snake venom. She later gives birth to a daughter whom the villagers call "The Devil's Baby" and in a fit of fear they end up burning the family's house down. Years later a Scotland Yard detective is sent to the village to investigate a rash of deaths that are caused by snakebite.