Norah Benson, Shirley MacLaine, is an upper-class Manhattan divorcee living with her two children, Carrie Benson, Lisa Kohane, and Peter Benson, David Elliott. One night Norah invites her younger brother Joel Delaney, Perry King, to a party hosted by her psychologist friend, Erika Lorenz, Lovelady Powell. Norah’s refined world collides with Joel’s bohemian outlook, and while they clash, the siblings share a deep bond forged after their mother’s suicide years earlier, with Norah acting as Joel’s guardian since then. The gathering offers a prelude to a chilling unraveling, as the two youths’ paths begin to diverge under the weight of unspoken family trauma.
Two days after the party, Joel fails to show up for a dinner Norah has planned at her home. Worried, she goes to Joel’s East Village apartment and finds him being escorted by police to the Bellevue Hospital psychiatric ward after an assault on the building’s superintendent. In Joel’s flat, Norah discovers a large switchblade knife and an esoteric hand symbol painted on the wall. She is soon met by Joel’s former girlfriend, Sherry, Barbara Trentham, who hints at Joel’s dark side. The apartment had previously belonged to Tonio Pérez, the superintendent’s son, a detail that threads into the story’s growing mystery.
Unable to recall what happened, Joel convinces the doctors that he was under the influence of hallucinogens, and he is discharged on the condition that he continue with psychiatric care. Norah arranges for him to meet Erika, who has known Joel most of his life, hoping to anchor him back to reality. During their sessions, Joel recounts his close friendship with Tonio Pérez, while Norah begins to welcome him into her home more often, trying to stabilize the situation. Yet the visitations of uncertainty persist as Joel’s behavior becomes increasingly erratic, and he begins to probe Norah’s private life, a sign that something darker is simmering beneath the surface.
The tension escalates when Joel’s offhand cruelties surface publicly—first in subtle, unsettling questions about Norah’s sex life, then at his own birthday party, where he unleashes a barrage of crude insults toward Norah’s Puerto Rican maid, Veronica, [Miriam Colon], provoking a volatile clash that unsettles the entire household. Veronica’s presence becomes a doorway into a broader community, hinting at the cultural tensions that thread through the film’s setting in Spanish Harlem and beyond.
With Veronica’s help, Norah seeks Don Pedro, [Edmundo Rivera Álvarez], a Santería practitioner in Harlem who agrees to aid in banishing Tonio’s alleged spirit, which he believes has possessed Joel’s body. Don Pedro arranges a ceremony to cast out the entity, attended by Tonio Pérez’s grief-stricken mother, who reveals that Tonio was a murderer and that his father disposed of Tonio’s remains after discovering his crimes. The ceremony ends inconclusively, largely because Norah remains skeptical about the supernatural, even as the ritual’s intensity lingers in the air.
Norah returns home to find Joel screaming in Spanish, an escalation that forces her to move the children to a beachfront vacation home in Long Island for safety, while Erika promises to help Joel from afar. The next morning, Norah discovers Erika’s severed head in the kitchen, and Joel stands nearby with his switchblade, now fully possessed by Tonio. Joel’s malevolent presence becomes a weapon as he torments Norah and the children, turning the house into a chamber of fear and control.
When Ted, [Robert Burr], arrives with the police, Joel forces Peter to strip and dance naked on a table, and compels Carrie to eat dog food, cutting her when she resists. Norah, gripping her own fear, fights to halt the assault, but Joel’s strength and rage overwhelm her. The nightmare peaks as Joel fatally wounds those who stand in his way, and the family’s safety hinges on a desperate confrontation with law enforcement. The police shoot Joel as he pursues the kids, ending his rampage, but not without leaving a lasting, unsettling tremor in Norah. In the aftermath, Joel dies in Norah’s arms, and her demeanor shifts to a chilling, emotionally distant resolve as she picks up Joel’s switchblade and brandishes it at the surrounding officers, leaving a haunting impression of a mother who has faced a darkness she may never fully comprehend.
