The River King

A seasoned police detective assigned to Gus Pierce's case. He is driven by a strong sense of duty but haunted by survivor's guilt from his brother Frank's suicide. The investigation tests his boundaries with authority, and he ultimately turns in his badge and burns Gus's suicide note to spare Carlin further pain.

Haddan School's photography teacher who becomes a crucial witness in the investigation. She urges Abel to be kind to Carlin and reveals key clues from the photographs. Though engaged to a dorm supervisor, she pursues honesty and eventually ends their relationship for personal reasons.

Seventeen-year-old Haddan School student, portrayed as a loner who is bullied by Harry and his Chalk House clique. His death triggers the investigation and lays bare the cruelty embedded in the campus' social structure. His note and the autopsy details reveal the mystery behind his final moments.

A Haddan School student connected to Gus and a witness to the cruelty of Chalk House. She shares crucial information about Gus's death, struggles with grief, and eventually confronts the truth about the school's cruelty. Her relationship with Gus's friend and pressure from the investigation weigh on her.

Leader of the Chalk House crew who torments Gus and others. He embodies the cruelty of the exclusive dorm and its secret society, and his actions catalyze the tragedy. His power over peers is challenged as the investigation proceeds and he is expelled.

Dorm supervisor and Betsy's fiancé, portrayed as a figure of authority within Haddan School. His role ties to the dorm’s culture and the perceived protection that allows cruelty to persist. He is confronted by the investigation when the truth threatens the school’s prestige.

Gus Pierce's father, who reveals that Gus did leave a suicide note, influencing the case's outcome. He represents a grieving parent’s perspective and the sentiment of trying to understand what happened.

Abel Grey's father, whose own past and relationship with Abel inform the detective's survivor's guilt and the personal stakes of the case.

The Dean of Haddan School, a figure connected to the school's administration and the social codes that protect the privileged. He represents the institutional layer that the investigation confronts.