Jodie is a young woman who operates under the guise of the perfect Beverly Hills housewife. In reality, she is Joanne Adams, a woman who recently completed a prison sentence and orchestrated her entire marriage to Dr. Roy Davies as a covert investigation. Driven by a traumatic childhood and fierce loyalty to her deceased older sister, Deborah, she meticulously cleans and maintains her home as a way to secretly search for evidence of her husband's guilt.

Roy is a wealthy, respected psychologist and bestselling author known for his expertise in relationships. Behind his polished public image and his reputation as a grieving widower, he maintains rigid control over his household. He demands perfection from his wife and uses his professional credibility to isolate the women in his life, often framing their distress as mental instability.

Marie is the longtime housekeeper for the Davies household. She is fiercely protective of her employer and intensely devoted to the memory of his first wife, Deborah. She treats Jodie as an unwanted intruder, constantly attempting to undermine her domestic efforts and warning her that she will not last long in the home.

Deborah was Roy's first wife, a beautiful woman whose life ended in a widely reported suicide. Before her death, she was known for her optimism and kindness, qualities that provided her younger sister with her only source of childhood comfort. Her sudden decline into apparent madness and reclusion remains the central mystery that drives the plot.

Veronica is a woman with ties to Roy's past, existing on the periphery of his marriage to Deborah. Her existence becomes a critical piece of evidence as Jodie builds a case regarding her husband's possible motives for murder. She represents a direct threat to the domestic stability that Jodie is trying to maintain for her investigation.

Meredith is a wealthy, class-conscious neighbor who considers herself a pillar of the local social elite. As the unofficial leader of Roy's friend group, she is fiercely protective of his reputation and idolizes the memory of his first wife. She treats service workers—and Jodie—with poorly disguised condescension.

Eileen is a member of Meredith's social circle, occasionally referred to collectively as "the harpies" by Jodie. She is slightly more observant than her peers but generally follows Meredith's lead in social situations.

Barb rounds out the trio of older, wealthy women who frequently visit the Davies home. She contributes to the echo chamber of gossip that insulates Roy from suspicion.

Dolores is Meredith's live-in housekeeper who lives on the property with her young son. She is hardworking and kind, contrasting sharply with the wealthy women who employ her. She recognizes Jodie's genuine domestic skills and forms a quiet camaraderie with her.

Mikey is the eleven-year-old deaf son of Dolores. He lives on Meredith's property and has a habit of sneaking into neighboring houses for snacks, making him a silent witness to the hidden realities of the affluent neighborhood.

Detective Bates is a law enforcement officer tasked with unraveling the violent events at the Davies household. He is methodical and observant, attempting to pierce through Jodie's carefully constructed domestic persona during his interrogations.