The Touch of Satan (1971)

On his way to California, Jodie decides on a whim to make a brief side trip to a farm, where he meets and falls in love with Melissa, the proverbial farmer's daughter. Or so it seems. In between the overlong dramatic pauses, we learn that Melissa is in fact a 120-year-old witch, and her remarkably spry "great-grandmother," Lucinda, is actually her sister, who has been pitchforking people to death in her spare time. When Lucinda murders a local policeman, things start to get real complicated for Jodie.