Content Warning: This section discusses life in and escape from a cult, abortion, and death.

Mia is the protagonist of the novel. She is the catalyst for all the major plot points, and her choices drive the experiences and decisions of the other characters. Her mother names her Mia as an act of rebellion—even though the children are supposed to belong to everyone, Ivy chooses to name her daughter a word that means “mine.” Mia is beautiful like her mother but with red hair rather than dark. She wears simple clothing throughout the novel, a holdover from her time at the Community, except for her mother’s red boots.

Although Mia is highly intelligent and has a deep love for literature, she is characterized by her emotions more than by her intellect. She is initially rebellious, searching for ways to escape the harsh requirements of the Community and willing to steal and hide possessions to protect herself. However, after her escape from the Community, she is haunted by her past, becoming withdrawn and isolated. She finds solace in the library, both as a child in Blackwell (where she discovers The Scarlet Letter) and as an adolescent volunteering at Constance’s public library, and in adulthood, as she successfully gets her dream job at the New York Public Library.