Jane is a newly married, upper-middle-class woman with a degree in sociology who takes a job as a social worker in impoverished Grace County, North Carolina. She is intelligent, warm, and determined to help her clients, though initially naive about the severe poverty they face. As she learns more about the state's eugenics program, she works to balance her professional duties with her personal moral convictions.

Ivy is a 15-year-old girl living in poverty as a tenant on Davison Gardiner's tobacco farm. She shoulders immense responsibility, working long hours in the fields while also caring for her diabetic grandmother and young nephew. Though social workers question her intelligence, she proves to be mature, fiercely loyal, and protective of her family, harboring secret dreams of moving to California.

Charlotte is the senior social worker who hires and trains Jane for the Grace County area. She is pragmatic, capable, and firmly believes in maintaining professional objectivity with her clients. She views the state's eugenics program as a practical tool to prevent further poverty, modeling the standard approach of the social welfare system in the 1960s.

Robert is a well-respected pediatrician and Jane's new husband. He holds traditional views on gender roles, preferring that Jane focus on domestic duties, charity work, and starting a family rather than pursuing a career. He is deeply concerned with social status and fears that Jane's work in impoverished areas will reflect poorly on him among his country club peers.

Mr. Gardiner is the wealthy owner of the tobacco farm where the Hart and Jordan families live as tenants. He holds significant authority over their lives, providing them with housing and employment. He presents himself as a caring and fair landlord who expresses concern for the well-being of his tenants, though he strongly advocates for the state's intervention in their reproductive choices.

Mary Ella is Ivy's 17-year-old sister who lives on the Gardiner farm and helps with the tobacco harvest. She is a young mother to a two-year-old son, William, and has been assessed by the state as having a low IQ. She has been sterilized without her knowledge or consent under the guise of an appendectomy, a medical intervention that causes deep distress for her family.

Winona, known as Nonnie, is the aging matriarch of the Hart family, acting as the guardian for her granddaughters, Ivy and Mary Ella, and her great-grandson, William. She suffers from diabetes and poor health, making her unable to work in the fields. She is strict and sometimes harsh, making difficult choices she believes are required for the family's survival, including consenting to state medical interventions.

Lita is a Black woman in her thirties who lives as a tenant on the Gardiner farm with her children. She is a hard-working and deeply devoted mother who voluntarily opted for sterilization through the eugenics program to ensure she could provide for the children she already has. She offers kindness and solidarity to Jane during her home visits.

Henry Allen is the teenage son of Davison Gardiner. He pursues a secret romantic connection with Ivy Hart, a tenant on his family's farm, defying the severe class differences between them. He dreams of leaving North Carolina and moving to California, frequently bringing Ivy gifts and promising her a different life.

William is Mary Ella's two-year-old son who lives with the Hart family. Due to the adults working long hours and Nonnie's failing health, William often lacks constant supervision, making him a focal point for the social workers' concerns about the family's capabilities.

Ann is the public health nurse assigned to the families in Grace County. She works closely with the social workers to monitor the physical health, hygiene, and reproductive status of the clients, frequently pushing for immediate medical interventions for the teenage girls.

Eli is Lita Jordan's 17-year-old son who works on the Gardiner tobacco farm. He helps support his large family through manual labor and occasionally interacts with Jane as she visits the farm.

Mrs. Gardiner is Davison Gardiner's wife and Henry Allen's mother. She bears a visible facial scar from a past altercation with Ivy's mother and strictly enforces the social and moral boundaries between her family and the farm tenants.

Lois is a woman Jane meets through her husband's social circles at the country club. Unlike the other wives, Lois is a former teacher who understands Jane's desire for a meaningful career and provides her with much-needed friendship and validation.

Gavin is a local lawyer and the husband of Jane's friend Lois. He moves in the same upper-middle-class social circles as Jane and Robert, offering professional perspective to Jane when she has questions about her work.

Paula is another social worker in Jane's office. She rigidly adheres to the agency's protocols and the eugenics program's goals, frequently warning Jane to remain objective and detached from her clients.

Brenna is Jane's stepdaughter, introduced in a later timeline sequence. She shares a close, trusting relationship with Jane and takes an active interest in the history of the families Jane once served.

Dr. Carson is a medical colleague of Robert Forrester. He refuses to prescribe birth control to Jane without her future husband's explicit permission, reflecting the strict gender and medical norms of the era.