In a secluded mansion, young art student Peggy Johns takes on the role of a housekeeper for the enigmatic artist Jeffrey Elliot. Upon arriving, she is introduced to Jeffrey’s stern and secretive mother, Mrs. Elliot. The atmosphere is unsettling, with rooms locked and sounds echoing throughout the house at odd hours. Peggy quickly becomes aware of a mysterious locked studio room that Jeffrey forbids her from entering. As Peggy adjusts to her duties, she learns of a family secret involving Jeffrey's sister Jennifer, who is said to have been institutionalized years ago. The household staff warn Peggy about probing too deeply, but her curiosity grows as she encounters strange occurrences around the estate.

Determined to uncover the truth, Peggy experiences chilling events that lead her to question her safety and the reality within the house. Unexplainable noises and eerie artifacts hint at a haunting presence that looms over the mansion. As Peggy strives to piece together the fragmented history of Jennifer and the Elliot family, tensions rise between her and Jeffrey, whose mood shifts dramatically between charm and menace. Mrs. Elliot’s cryptic demeanor and tight grip on family secrets add layers to the tension-filled environment. Peggy's persistence in unveiling the family's dark past sets her on a harrowing journey, ultimately revealing deeper, shocking truths about the family and herself.