Civil is a 23-year-old recent nursing school graduate from a middle-class Black family in Montgomery. She takes a job at a family planning clinic intending to help poor women, but her sheltered upbringing heavily influences her worldview. She drives a new car gifted by her parents but secretly swaps it for an older vehicle to avoid standing out at work. She carries deep personal guilt surrounding a recent medical decision and frequently oversteps professional boundaries in her eagerness to rescue others.

Tyrell is Civil's ex-boyfriend and the son of close family friends. He recently graduated from college and gave the commencement address for his class. Coming from an educated family of lawyers, he shares Civil's comfortable background but exhibits a more easygoing demeanor. He supports Civil through her early career challenges and helps her investigate the medical practices at the clinic.

Alicia is a newly hired nurse at the Montgomery clinic. Unlike Civil, she comes from a working-class background and relies heavily on her job for financial stability. She left her family home after being forced to keep her mother's affair a secret. She shares Civil's desire to help their patients but approaches her employment with a more pragmatic mindset.

Mace is the 33-year-old widowed father of Erica and India. He works long hours on a white farmer's land and struggles to provide for his family following the death of his wife. He is illiterate and initially distrusts government workers, finding it difficult to accept outside charity.

Patricia, commonly referred to as Mrs. Williams, is the 62-year-old matriarch of the Williams family. She does her best to care for her granddaughters despite living in deep poverty. She possesses a keen understanding of class dynamics and remains highly observant of outsiders offering help, serving as the emotional glue holding her family together.

Mrs. Seager is the white supervisor of the Montgomery family planning clinic. She manages eight Black nurses and views the clinic's mission through a highly controlling lens. She firmly believes she knows what is best for the poor women who visit the clinic, enforcing aggressive birth control policies.

Erica is Mace's 13-year-old daughter. Since the death of her mother, she acts as the primary caretaker and voice for her younger sister. She is highly observant and protective, carrying emotional and physical burdens far beyond her years.

India is Mace's 11-year-old daughter. She is nonverbal and developmentally challenged, relying heavily on her older sister for communication and safety. Despite her challenges, she expresses herself clearly through actions, showing a love for mechanical horse rides and dogs.

Lou is a young, white attorney who takes on a complex medical case. His wife is a lawyer in Selma, and he demonstrates an earnest dedication to his work. He collaborates closely with Civil and the family, treating them with professional dignity.

Anne is Civil's 23-year-old adopted daughter. She recently graduated from college and serves as the primary audience for Civil's recollections of the past, absorbing the history of Montgomery and her mother's early life.

Dr. Townsend is Civil's father and a respected medical doctor in Montgomery. He provides a comfortable, middle-class life for his family. He cautions Civil against letting her self-righteousness blind her to reality, warning her not to treat the poorer members of their community as a project.

Mrs. Townsend is Civil's mother, a painter who spends most of her time isolated in her backyard art studio. She struggles with depression and maintains a somewhat distant relationship with her daughter, though she occasionally provides practical help like housing contacts and cash for furniture.

Val is an older, experienced nurse at the family planning clinic. She is highly protective of her steady employment and warns Civil against asking too many questions about the clinic's practices or Mrs. Seager's authority.

Miss Pope is a university librarian and an early feminist mentor to Civil. She provides vital historical context regarding medical experimentation on Black Americans, helping the younger generation understand the broader implications of their clinic's procedures.

Mrs. Ralsey is Tyrell's mother and a prominent attorney. She is the only woman to establish a law firm in her town, working alongside her husband. She uses her legal expertise to review the medical practices Civil discovers.

Mr. Ralsey is Tyrell's father and an attorney working at the law firm he shares with his wife. He is quick to draw historical parallels between modern medical practices and past abuses in Alabama.

Constance is the deceased wife of Mace and mother to Erica and India. Her death from breast cancer precipitated the family's decline into severe poverty, leaving an enduring emotional void in their household.

Aunt Ros is Civil's aunt and Mrs. Townsend's sister. She is observant and highly proactive, easily recognizing her sister's deep depression and immediately stepping in to provide practical care and a supportive community.

Sister LaTarsha is a Black nun who helps operate an educational facility tailored to individual student needs. She introduces India to specialized activities while offering Civil wise counsel about emotional burnout.

Eugenia is Mrs. Seager's adult daughter. She bears a strong physical resemblance to her mother and grapples directly with the legacy of her mother's professional conduct at the clinic.

Nellie is Constance's cousin. She provides a warm, loud, and highly affectionate environment that sharply contrasts with Civil's quieter upbringing. Her household offers the Williams family a brief respite and a strong sense of extended kinship.