Kinsey Millhone, the protagonist and narrator of the novel, embodies a strong, determined personality that navigates a series of complex investigations. Millhone is a private investigator in her early 30s, reflecting a modern approach to her work, built on a foundation of professionalism and a keen eye for detail. She operates in a world often dominated by men, showcasing a fierce independence and self-reliance that not only defines her character but also breaks away from traditional gender norms of the time.

Millhone has a complex personal history. She has experienced loss, having endured the dissolution of two marriages, a backdrop that offers a rich layer to her personality, where resilience meets vulnerability. Her relationships in the novel, both professional and personal, navigate a spectrum of emotions, offering a glimpse into her inner world that oscillates between a guarded disposition and a willingness to connect genuinely. Her background in law enforcement, highlighted by her training as a police officer, has equipped her with the skills and the mindset to dive deep into criminal investigations. She has a meticulous approach to her work, often going above and beyond to unearth the truth, a trait that is vividly showcased in her relentless pursuit of clues and answers in the investigation central to the novel.