The wonderfully suspenseful psychological drama Spiral Staircase is the prototype of the "old dark house, lady in distress" thriller, full of dark corners, flickering candles and featuring a mysterious, menacing killer whose true identity remains hidden until the end. Helen Capel (Dorothy McGuire), mute because of a childhood trauma, cares for the owner of the house, the wealthy Mrs. Warren (Ethel Barrymore), a demanding, widowed invalid. Helen has quietly fallen in love with one of Mrs. Warren's sons, Dr. Parry (Kent Smith), who she believes to be a gentle and understanding man. Helen's peaceful life is changed forever when three local women, all with physical handicaps, are found murdered. The movie builds to a suspenseful conclusion as Helen finds herself in the midst of a life-and-death battle in the house, as the true identity of the murderer is revealed. Dorothy McGuire is exquisite as the innocent, sweet Helen and gives a totally convincing performance in the difficult role. She uses her expressive face to perfectly convey Helen's emotions, fear and ultimate bravery. Ethel Barrymore won an Academy Award nomination for her performance as Mrs. Warren and plays the difficult "Grande Dame" with great relish. Director Robert Siodmak, noted for his stylish direction of atmospheric suspense films, uses all his plot devices with great skill and craftsmanship, increasing the suspense and sense of foreboding as Helen is observed through the eyes of her stalker, who the audience sees only as a pair of menacing eyes.