When his brother disappears, Robert Manning (Mark Eden) pays a visit to the remote country house he was last heard from. Althought his host Squire Morley (Christopher Lee) is outwardly welcoming, and his housekeeper's beautiful niece Eve (Virginia Wetherell) is willing to fulfil his needs. Manning detects a feeling of menace in the air with the legend of Lavinia (Barbara Steele), the Black Witch of Greymarsh, hanging over everything. Will the village's renowned expert on witchcraft, Professor John Marshe (Boris Karloff), be able to shed light on the wicked going-ons at Craxted Lodge?