Maria is the protagonist of the novel; a lengthy portion of the text includes a narrative of her past, which is presented in her first-person voice. At other times, the omniscient, third-person narrator provides insights into Maria’s thoughts and feelings. At the start of the plot, Maria is 26 years old, has been married for about six years, and has an infant daughter whom she loves very much. Maria comes from a well-off family and has been well-educated; she enjoys reading and writing and can read multiple languages. Her social class has given her some key advantages, including access to education and potentially enough money to live an independent life, but it has also made her quite docile and unaccustomed to making her own decisions.

Despite being a wife and mother and having already endured a lot of suffering, Maria is presented as somewhat naïve, idealistic, and sentimental, especially around notions of romantic love. For the initial period that she is imprisoned, she is exclusively focused on getting out of the asylum and reuniting with her daughter; she shows intelligence, boldness, and strategic thinking in her attempts to do so.