Jez is an 11-year-old girl living on Wadmalaw Island in 1960s South Carolina. She is academically gifted, having skipped a grade, but struggles socially at school where other children tease her. Following her grandmother's death, she begins learning her family's traditional rootworking practices to protect her loved ones.

James, commonly known as Jay, is an 11-year-old boy who begins studying rootwork alongside his twin sister. He is more outgoing and socially comfortable than Jez, though he finds schoolwork more challenging. He spends his free time building model airplanes and wonders why their father left years ago.

Janey runs the family farm, selling crops and homemade goods to support her children following the disappearance of her husband. Though she respects her family's Gullah Geechee heritage, she chooses not to practice rootworking herself. She prioritizes formal education for her children, hoping it provides them safer opportunities in a prejudiced society.

Doc is the last remaining active rootworker on the Turner farm after his mother's passing. He runs a shop where he dispenses advice, fertilizers, and traditional remedies to the local community. Recognizing the physical dangers facing Black families in the Jim Crow South, he insists on teaching his niece and nephew traditional protective magic.

Annie, affectionately known as Gran, was a highly respected rootworker before her passing. She provided remedies and spiritual protection for her neighbors. She maintained a uniquely close bond with Jez, leaving behind a handmade doll and a legacy of powerful magic.

Deputy Collins is an aggressive local police officer. He frequently abuses his authority to terrorize Black families and specifically targets rootworkers, regularly searching homes without warrants. He constantly patrols near the Turner farm, creating a physical threat over the family's daily life.

Susie is a new student at Jez's school. She approaches Jez when the other children ostracize her, quickly forming a bond over shared lunches. Susie mentions her family frowns upon root magic, complicating her ability to visit Jez's home directly.

Lettie is a student who frequently bullies Jez. She mocks Jez's clothes and heavily criticizes rootworking, calling Jez a witch and regurgitating prejudices against traditional country practices.

Sheriff Edwards is the newly appointed local law enforcement leader. He presents himself as polite and attempts to smooth over tensions, but he frequently cites procedural rules to excuse his inaction regarding his deputy's abusive behavior.

Miss Corrie is the school nurse. She buys rootwork remedies from Doc and encourages Jez, explaining that while her own family abandoned their rootworking traditions, she views Jez's abilities as special.

Miss Watson is a schoolteacher who emphasizes the importance of reading and writing one's own history. She introduces her students to poetry by Black authors, creating a supportive classroom environment.

Daniel is Janey's husband and the twins' father. He disappeared when the children were six years old, leaving behind a void in the family and questions about his sudden departure.

Dinah is a small handmade doll given to Jez by her grandmother. Activated by Gran's breath, the doll possesses a unique spiritual connection to the family's magic.

Tony is a boy at school who befriends Jay. He suggests they become blood brothers, an act that causes friction between the twin siblings.

Mr. Benjamin is a local community member who visits Doc. He mourns the recent loss of his daughter. His presence demonstrates the tight-knit nature of the community.