Sandra Harrison as Nancy
Six weeks after her mother dies a girl's father remarries and stepmom has the kid sent off to a school for girls. She doesn't really fit in and there just happens to be a teacher that hypnotizes her for some ludicrous theory of supernatural power for the benefit of mankind. The girl turns into a vampire with pointy ears, a widow's peak, pasty face and pointy teeth. Soon the killings begin and the police are baffled.
Blood of Dracula (1957) .... Nancy Perkins
... aka Blood Is My Heritage (1957) (UK)
... aka Blood of the Demon (1957) (Canada: English title)