Isis is an 11-year-old girl living in a small Florida town near Orlando. She possesses a highly active imagination, frequently daydreaming about fairytales, princesses, and mythological figures like Hercules. Preferring play and exploration over domestic chores, she exudes a natural joy that charms the surrounding community. Her curiosity and desire for freedom often place her at odds with the strict expectations of her household.

Grandma Potts is the stern, practical matriarch of the Watts family. Having experienced the harsh realities of the American South, she strictly enforces domestic duties, gender roles, and respectable behavior to protect her family. She maintains a rigorous routine confined to the home and frequently threatens her granddaughter with whippings to ensure compliance. She has a distinctive straggling beard on her chin that catches Isis's attention.

Helen is a wealthy white woman traveling through the Florida countryside. She does not speak in the local dialect and uses her financial privilege to handle minor conflicts, such as replacing a ruined tablecloth. She finds herself entirely captivated by Isis's joyful, free-spirited demeanor, viewing the young girl as a source of brightness that she wishes to absorb.

Joel is Isis's older brother who lives in the same household under their grandmother's care. As a boy, he enjoys a privileged position in the family, free from the heavy domestic expectations placed upon his sister. He occasionally conspires with Isis in childish mischief, such as an ill-fated attempt to shave their grandmother's whiskers, though he largely escapes the resulting punishment.

John Watts is Isis and Joel's father. While he maintains an absent presence in the day-to-day events of the household, he represents ultimate authority and discipline. His mother, Grandma Potts, invokes his name and utilizes his belongings, such as his shaving razor, to maintain order.

Jim Robinson is a local white cattleman who frequently travels past the Watts family home. He is fond of little Isis and indulges her love for the road by letting her ride on the back of his saddle until she is called back to work.

Harry is one of the white men traveling with Helen through the Florida countryside. He observes the interaction between Helen and Isis, jokingly commenting on how quickly the young girl has bonded with his companion.