In Los Angeles, 1967, Mr. Browning, portrayed by Sam Anderson, and his younger wife, Jenny, played by Kate Siegel, visit the home of fortune teller Alice Zander, brought to life by Elizabeth Reaser. During the séance Alice conducts, Mr. Browning seeks to communicate with his deceased wife, while Jenny remains skeptical, believing they are being swindled. As tensions rise, a spirit, disguised as the late wife, frightens Mr. Browning, prompting an emotional show of fear. When Mr. Browning attempts to pay Alice, she declines, feeling guilty for their ruse.
Unbeknownst to them, the entity haunting the séance is Alice's own teenage daughter, Paulina, depicted by Annalise Basso, with her younger sister, Doris, played by Lulu Wilson, aiding in the deception. After being scolded by Alice for costing them potential earnings, Paulina defends her actions. As events unfold, Paulina sneaks out to join her friends Ellie, played by Halle Charlton, and Mikey, portrayed by Parker Mack, where they toy with a Ouija board, only to send one friend into a panic.
While the girls are at school, Alice naively seeks her own Ouija board, believing it could boost their business. That night, she accidentally connects with a spirit named Marcus through Doris, who becomes a medium for strange and chilling responses from the other side, leaving Paulina both perplexed and intrigued. Doris, in her quest to communicate with their deceased father, Roger, breaks the cardinal rule of the game by playing alone, leading to haunting developments.
Father Tom, played by Henry Thomas, calls Alice to discuss Doris's unusual homework, written in cursive, showcasing her sudden change in behavior and the development of uncanny abilities tied to the spirit world. As mysterious occurrences escalate, including a notice of foreclosure, Doris presents her mother and sister with money she claims to have found – a supernatural twist that raises questions about the spirit's demands.
In an attempt to tap deeper into the otherworldly, Alice and Doris hold a séance with Tom. The answers they receive are nothing short of chilling, uncovering dark secrets tied to the house and the past of its previous occupants. Events take a sinister turn when Mikey visits and becomes ensnared by the entity, further trapping the family in a nightmarish scenario.
The climax unfolds with furious supernatural elements as the girls confront the vengeful spirits. When Alice desperately pleads for her daughters' safety, a harrowing possession occurs, leading to a tragic conclusion. Two months later, we find Lina, portrayed by Lulu Wilson, grappling with the aftermath in a mental hospital, where she attempts to reconnect with her lost sister through dark practices.
As the story closes, an older Lina, played by Lin Shaye, faces her own demons while hinting at her return to a life intertwined with the supernatural, setting the stage for chilling possibilities yet to unfold.
