Honey is a sixteen-year-old girl living in rural Kentucky in 1953. Like her birth mother and her adoptive mother, she carries a genetic condition called methemoglobinemia that turns her skin blue—though it only affects her hands and feet. Faced with the threat of being sent to a juvenile prison after her parents' arrest, she seeks independence by applying to become a Pack Horse librarian.

Pearl is a nineteen-year-old fire lookout from Somerset who takes a demanding job at the Troublesome Creek watchtower. She quickly befriends Honey, bonding over their shared love of reading and fiercely protective instincts. Capable and independent, Pearl faces sexism and harassment from men who resent her holding a position they believe belongs to a man.

Perry is a violent, deeply prejudiced coal miner in Troublesome Creek. He holds aggressive, sexist views, frequently harassing his female coworkers and resenting Pearl for taking the fire lookout job. He actively despises literature and directs his bigoted anger toward anyone he considers different, especially the "Blues."

Loretta is a ninety-two-year-old family friend who steps in to help Honey when her parents are arrested. A devout Christian who prefers the Bible above all other reading, she nevertheless values literacy and education, having learned to read at a Moonlight School. She provides Honey with a safe haven and maternal comfort.

Devil John is a local moonshiner who operates outside the law but holds a strict personal code of ethics. He intervenes to protect Honey from state authorities, claiming her as his own daughter to prevent her from being sent to a juvenile facility. He offers pragmatic, if sometimes outdated, solutions to keep her safe.

Mr. Morgan is a dedicated lawyer working on behalf of Honey and her imprisoned parents. He helps file the necessary paperwork to keep Honey out of the House of Reform and researches legal avenues for her to gain independence. He serves as Honey's primary representative within the formal legal system.

Bonnie is a widowed mother who works in the coal mines to support her son. Having previously hired Honey as a babysitter, she holds fond feelings for the young woman. In the male-dominated mines, Bonnie faces severe sexual harassment and physical violence, prompting her to band together with other women for mutual protection.

Wrenna is a young girl living with a local healer after the death of her parents. She is rarely seen without her fiercely protective pet rooster. She frequently roams the woods and relies on a close network of female friends to shield her from the cruelty of local men.

Cussy, known as "Mama" to Honey, is the original Book Woman of Troublesome Creek. As one of the last "Blues," she is arrested alongside her white husband for violating Kentucky's discriminatory miscegenation laws. She passes her profound love of literature, herbalism, and survival skills down to her adoptive daughter.

Papa is Honey's white adoptive father, a timber businessman who is violently arrested for his marriage to a "Blue" woman. He makes gloves for Honey to hide her blue hands and ensures she has a safe place to hide when the authorities come for their family.

Francis is a polite, friendly young man who works at the local store. He takes an immediate liking to Honey, offering her free items and teaching her how to use a payphone. He proves to be a protective presence, willing to physically defend his female relatives from abusive men.

Guyla Belle is the deeply oppressed wife of Perry Gillis. Trapped in an abusive marriage, she quietly defies her husband by setting up a secret system for Honey to deliver library books to her, seeking comfort and power through reading.

Carson is Devil John's son who helps protect Honey from the social worker. He pragmatically offers to marry Honey purely to shield her from the law, even though he is already seeing another girl, demonstrating the community's willingness to exploit loopholes for protection.

Mrs. Wallace is a prejudiced social worker assigned to Honey's case. She actively dehumanizes Honey by referring to her as "it" and is determined to see the teenager incarcerated, weaponizing her authority against the "Blues."

Amara is a practical, dedicated frontier nurse who travels through the hollers treating patients. She is unafraid to stand up to violent men and provides medical care to the vulnerable women of Troublesome Creek.

Doc is a local physician who provides Honey with critical information about her imprisoned mother. He offers her a safe place to stay and leverages his professional status to push back against the prison administration.

Alonzo is Loretta's nephew, a man who struggles heavily with alcoholism. Despite his aunt's clear wishes to leave her property to Honey, his financial desperation and drinking habits lead him to make selfish decisions regarding her estate.

Junia is a stubborn, highly intelligent pack mule that originally belonged to Cussy. She acts as a fierce protector for Honey, using her teeth, hooves, and even bodily functions to ward off threats, though she frequently demands cookies for her cooperation.

Tommie is Wrenna's pet rooster. After ingesting a special lodestone given to Wrenna by a healer, the bird acts as a fiercely territorial guardian, trained to respond to specific calls when his "hens" are in danger.

Miss Foster is the librarian in charge of hiring for the newly revived Pack Horse Library Project. She strictly regulates the library's collection to ensure moral propriety but strongly supports Honey's employment.