Content Warning: This section of the guide references the waterboarding torture of a teenager.

Marcus is the protagonist of Little Brother, and Doctorow’s employment of first-person limited point of view, which sometimes transitions to second-person, allows the story to be told through the lens of Marcus’s perceptions. Marcus is a round and dynamic character, whose story follows a coming-of-age arc. As a teenager, he is an unreliable narrator; his naïveté causes him to misinterpret other character’s motivations, and the press often betrays his idealism in their focus on profit over objectivity. However, it is his idealism that informs his decision to wage war against the DHS and that drives the plot forward. Marcus is a senior at Cesar Chavez High School, where he engages in an ongoing feud with the vice-principal, Fred Benson. His best friends are Darryl, Van, and Jolu, who are fellow team members in the alternate reality game Harajuku Fun Madness. His father, Drew, provides an opposing perspective on the issues of privacy and freedom of speech—Drew has no problem forfeiting privacy for safety—while his mother, Lillian, provides a buffer between Marcus and his father.