A once-again rehabilitated Norman Bates, Anthony Perkins, is now married to a psychiatrist named Connie Donna Mitchell and is expecting a child. Norman secretly fears that the child will inherit his mental illness. One evening, he hears radio talk show host Fran Ambrose, CCH Pounder, discussing the topic of matricide with her guest Dr. Leo Richmond, Warren Frost, Norman's former psychologist. Norman calls into the radio show, using the alias "Ed", to tell his story. The scene shifts between present tense and a series of flashbacks, gradually revealing the origins of a crime that still haunts him.
Norman's narrative unfolds as a mosaic of memories from the 1940s and 1950s, occasionally out of order. When Norman is six years old, his father John dies, leaving him in the care of his mother, Norma Bates Olivia Hussey. Norma dominates the household with a harsh, controlling presence, and she subjects Norman to brutal punishments for the slightest infraction. She beats him, even exposes him to rain while naked, and instructs him in a view of sexuality as sinful. She dresses him up in her clothes, smears lipstick on his face, and imposes an unsettling dynamic during acts of sexual tension, including incestuous foreplay. She also makes him urinate like a girl, squatting over a pitcher, a punishment he endures as part of her grip on him. The motel’s fortunes wobble under financial stress, and Norma’s mood darkens as she channels her frustration into harsh discipline.
The family unit remains secluded until, in 1949, Norma becomes engaged to a brutish man named Chet Rudolph Thomas Schuster. Chet openly bullies Norman, and Norma seems to take pleasure in the arrangement. Driven to a breaking point by jealousy and repeated abuse, Norman murders them both—poisoning their iced tea—and then disposes of Chet’s body while stealing and preserving his mother’s corpse. This act catalyzes a chilling split in Norman’s psyche, as he temporarily “becomes” his mother to suppress the guilt of the deed. When the "Mother" voice takes over, he clothes himself in his mother's garments, wears a wig, and speaks in her voice, committing further killings. As "Mother," he murders Holly Sharen Camille and Gloria Bobbi Evors, two local women who linger at the motel with romantic interest in him. After each murder and other acts, Norman awakens with the belief that "Mother" is responsible, and he destroys the evidence to hide the truth.
In the present day, Dr. Richmond recognizes "Ed" as Norman and urges Fran Ambrose to trace the calls. His concerns are dismissed by the outside world, but Norman grows increasingly anxious that he might slip into madness and kill again. He tells Fran that Connie has become pregnant against his wishes and that he fears the birth could produce another “monster.” Yet he also acknowledges a dangerous desire to protect his wife and unborn child from a fate like his own. He confesses that he thinks he can control the impulses, cultivating a complacent belief that the past can be reined in.
Norman eventually takes Connie to his mother’s old house, intending to finish what he started by killing her and the unborn baby. Connie confronts him with courage and clarity, reminding Norman that freedom of choice lies in his hands and that their child can be guided toward a different path. Her insistence gives Norman a moment of reckoning: he acknowledges that his choices matter and that he has the capacity to shape the future. He puts down the knife and, in a dramatic turn, sets fire to the house that housed so much of his misery. As the flames rise, he experiences a final, haunting vision—his victims, Norma, and even himself preserving her corpse—before he barely escapes the burning wreck alive.
When daylight returns and investigators survey the ruins, Norman declares that he is finally free of his mother. He and Connie walk away, but the house’s cellar doors remain, creaking closed on a rocking chair that continues to move, as if Mother herself is trapped beneath the ashes, screaming for release. The final sound—a baby’s cry—echoes as the screen cuts to black, leaving the question of Norman’s fate suspended in the aftermath of the blaze.
