Anna is a New York City-based actress experiencing a sudden surge in fame following her role in the film "The Auteur". She undergoes the strenuous process of in vitro fertilization (IVF) to conceive a child with her husband, Dex. Desperate to become a mother, she endures physical pain and severe anxiety, exacerbated by mysterious occurrences that make her feel unsafe. As strange events surround her pregnancy, she struggles to make the medical professionals and her own husband believe her direct experiences.

Dexter is a successful New York businessman and Anna's husband. He superficially supports Anna's IVF journey by attending appointments and managing her medications. However, he remains emotionally distant and frequently dismisses Anna's concerns, preferring his own assessment of reality over her direct experiences. His tendency to gaslight Anna leaves her feeling isolated during a vulnerable time.

Siobhan is a highly successful, famous actress and Anna's closest confidante. She operates with an effortless confidence that Anna deeply admires. Serving as the primary source of emotional support in Anna's life, Siobhan listens to her fears without judgment or dismissal. Their friendship offers Anna a safe space away from the demanding men and medical institutions controlling her life.

Io is a mysterious woman who begins appearing around Anna during the early stages of her IVF treatments. She runs an online blog focused on pregnancy and fertility clinics, drawing Anna's suspicion. Decades earlier, in 1987, she worked as a surrogate mother to earn money, enduring a nightmarish pregnancy that left her searching for answers about what happened to her body.

Dr. Hill is the primary physician managing Anna's IVF treatment at the fertility clinic. While she maintains a kindly, professional exterior, she consistently minimizes the severe physical pain Anna experiences during and after her procedures. Her clinical approach leaves Anna feeling unheard and medically invalidated.

Emily is Anna's demanding publicist. Following the sudden success of Anna's latest film, Emily aggressively schedules media appearances and pushes Anna into the public eye. She prioritizes career momentum over her client's physical and emotional well-being during the arduous IVF process.

Talia is the CEO of the company where Dex works. She is also undergoing IVF treatments and offers Anna a brief sense of solidarity. She generously allows Anna and Dex to stay at her unoccupied Southampton home to escape the pressures of New York City, though she occasionally drops unsettling hints about Dex's past.

Cora is the receptionist at the clinic where Anna receives her IVF treatments. She manages the front desk and patient appointments, occasionally interacting with the mysterious individuals who linger around the facility.

Olympia is a friend of Siobhan's who works at a birthing center. She steps in to field Siobhan's calls, inadvertently becoming Anna's point of contact during a moment of intense vulnerability.

Kamal is a professional bodyguard hired by Anna and Dex following a series of disturbing incidents. He drives Anna to her appointments and helps secure Talia's house, taking Anna's security concerns far more seriously than Dex does.

Meg is an ultrasound technician who attends to Anna during a severe medical scare. Her brief interaction with Anna becomes a source of deep confusion when hospital staff later fail to recognize her name or employment status.

Dr. Crawford is a hospital physician who confirms Anna's medical status following an emergency. Like many male doctors in Anna's life, he speaks to her in a condescending, soothing tone that invalidates her direct experiences and memories of the hospital staff.

Adeline is Dex's ex-wife. She exists in the periphery of Anna's life as an unspoken subject that Dex refuses to discuss. Her continued friendship with Talia leaves Anna feeling disconnected from her husband's history.

Frank is the Chief Financial Officer at Dex's company. He joins the couple for a strained dinner early in Anna's IVF journey.

Gracie is Siobhan Walsh's daughter. She contacts Anna to inform her about her mother's sudden hospitalization.

Abigail is the lady of Arden House in the late eighteenth century. Following a difficult conception aided by folk remedies, she experiences a traumatic and horrifying childbirth.

Elizabeth is a maid serving at Arden House in 1789. She witnesses the disturbing aftermath of Abigail Rowe's secretive delivery.

Judy is a 42-year-old woman in the 1950s who discovers she is unexpectedly pregnant. Despondent over her financial situation, she soon finds a mysterious woman living in her attic who promises to help.

Maude is Judy Marshall's neighbor in 1957. Rather than comforting Judy about her pregnancy fears, Maude warns her to stay quiet to prevent others from taking her baby.

Lucy is a pregnant woman in 2007 who feels entirely dismissed by her doctors. Desperate for relief from her severe pregnancy pain, she turns to unconventional folk methods involving dolls.

Josie is a stranger who approaches Lucy Washington in 2007. She provides Lucy with specific instructions on how to use dolls to mitigate the physical suffering of pregnancy.

Viviana is a 16-year-old girl in the late 1970s who becomes pregnant. Unable to tell her strict Catholic parents, she attempts a magical abortion ritual that quickly goes wrong.

Sofia is Viviana Torres's friend in 1978. She facilitates a connection between Viviana and her great aunt, a bruja who knows magical rituals.

Betty is a new mother in the 1830s who exhibits erratic, animalistic behavior following the birth of her child. She lives in constant terror that unseen forces are trying to steal her baby.

Charles is Betty Anderson's husband in 1833. He fails to understand his wife's postpartum terror and summons her friend to intervene.

Frances is Betty Anderson's friend in 1833. She visits the house to investigate Charles's claims and finds Betty in a deeply wretched state.

Alice is a pregnant woman in the 17th century suffering from monstrous cravings. She watches the hanging of a midwife, entirely convinced the woman cursed her unborn child.

Margaret is a 17th-century midwife accused of witchcraft due to a hand-shaped birthmark. She previously treated Alice Parsons with anise seeds and honey before facing execution.