Zofia Nowak is the protagonist of The Keeper of Hidden Books. The novel is narrated from a third-person limited perspective, following Zofia’s thoughts and experiences. This perspective shifts in the epilogue, which is narrated by Zofia in the first person. Zofia is a passionate reader and lover of books. Although she has not finished high school when the novel begins, she already spends most of her time at the library, and she gets a job there after the Nazi invasion prevents her from continuing school. Zofia’s dedication to the library and its collections demonstrates her patriotism, her belief in The Unifying Power of Literature, and her desire to help her community proactively.

Zofia, a Polish girl, is 17 when the novel begins. Quiet and thoughtful, she has a strong moral compass and always does what she thinks is right. She is pretty but quiet; when Darek compliments her on her looks, she is taken aback because she is not used to such attention. Zofia resists the potential for a romance with Darek until the end of the novel, and this reticence reflects her seriousness and the utter dedication with which she protects the library’s collection and helps Janina.