The Spiral Staircase (1975 film)

The Spiral Staircase is a 1975 British film directed by Peter Collinson, starring Jacqueline Bisset and Christopher Plummer. It is a remake of the 1945 film The Spiral Staircase.

She visits the home of her elderly, invalid grandmother, and meet her uncle, Joe Sherman, a respected psychiatrist, but the visit turns into a nightmare as she encounters his brash brother Steven, a pretentious Southern belle named Blanche, and a number of other mysterious characters in a house where everyones life seems to be in grave danger.

Source: Wikipedia