The Night Evelyn Came Out of the Grave (1971)

A wealthy English lord is suffering a mental breakdown following the death of his red-headed wife Evelyn, whom he feared was cheating on him. He scours local bars and dives for lovely redheads willing to come to his decaying castle in the country, where he seduces them, then tortures and kills them. His friend the doctor talks him into remarrying to help heal his slowly-rotting mind, which he does--but are the doctor's orders what he really needs?