Minnow is a 17-year-old girl who recently emerged from a patriarchal cult in the Montana wilderness missing both of her hands. Incarcerated at the Missoula County Juvenile Detention Center for assault, she guards the secrets of her past. She strikes a deal with an FBI psychologist to share her story in exchange for a parole recommendation. Raised in strict isolation and denied basic education, she possesses an instinct for survival and a growing curiosity about the outside world.

The Prophet is the authoritarian leader of the Community, a religious cult isolated in the Montana wilderness. He maintains absolute control over his followers by forbidding reading, strictly regulating marriage, and punishing dissent with extreme physical violence. He demands absolute loyalty and manipulates his followers' beliefs to satisfy his desires for power.

Angel is Minnow's cellmate at the juvenile detention center, serving a long sentence for killing her uncle in self-defense. Hardened by her time in the system, she understands the unwritten rules of the mixed-offender facility. She acts as a protective figure for Minnow, teaching her prison slang and sharing scientific facts about the universe that challenge Minnow's religious upbringing.

Dr. Wilson is an FBI forensic psychologist investigating the destruction of the Community and the Prophet's death. He approaches Minnow in juvenile detention with a transactional offer: his recommendation for her parole in exchange for the truth about the cult. Professional and observant, he attempts to break through Minnow's guarded exterior to uncover the events that led to the cult's violent end.

Jude is a teenager living outside the Community's boundaries with his father. Despite the Prophet's teachings that outsiders are cursed and evil, Jude is kind, literate, and empathetic. He owns books and a guitar, introducing Minnow to a broader world and offering her a relationship based on mutual care rather than patriarchal control.

Samuel is Minnow's father, a former factory worker who moves his family into the wilderness to join the Community. As a loyal deacon, he enforces the Prophet's strict rules within his own family. His blind faith completely overtakes his paternal instincts, leading him to prioritize obedience to the cult over the safety of his children.

Constance is Minnow's younger half-sister and the first child born in the wilderness settlement. Raised entirely under the Prophet's doctrines, she represents the ideal, fully indoctrinated cult member. Minnow feels a protective bond toward her and views her as untainted by the outside world.

Waylon is Jude's father, a man living in self-imposed exile in the forest outside the Community. He struggles with alcohol use and carries the weight of past family tragedies. He operates on the fringes of the cult's territory, maintaining a tense existence near the Prophet's followers.

Philip is a young man with paranoid schizophrenia who encounters Minnow under a bridge shortly after her escape. During an episode off his medication, he grabs Minnow, triggering a severe trauma response that results in her brutally assaulting him.

Benny is a guard at the Missoula County Juvenile Detention Center. He maintains order in the facility but shows occasional moments of fairness and familiarity with the long-term inmates, particularly Angel.

Bertie is a teenage girl in the Community who defies the Prophet's ban on female literacy by keeping a secret book of fairy tales. Her quiet rebellion provides Minnow with her first exposure to reading and the possibility of independent thought.

Miss Bailey is a reading teacher at the juvenile detention center. She introduces Minnow to phonics and children's literature, providing a supportive environment where Minnow can reclaim the education denied to her by the cult.

Krystal is a tall, aggressive inmate at the detention center who uses intimidation to establish dominance. She targets Minnow, leading to violent confrontations within the facility.

Tracy is an inmate who leads the Christian youth group at the detention center. She uses her faith to cope with her environment and tries to bring other girls, including Minnow, into the fold.

Juanita is Minnow's public defender. She argues self-defense during Minnow's assault trial, attempting to contextualize her client's actions within her extensive history of trauma.