Based on the acclaimed novel by Keigo Higashino, Byakuyakou follows the tragic and intertwined lives of Ryoji Kirihara and Yukiho Nishimoto over the course of two decades. Their connection begins in childhood following a gruesome murder, which sets them on a path of moral ambiguity and cold-blooded survival. As they grow up, they remain physically distant to protect their secret, yet their lives are inextricably linked by a series of crimes and manipulations designed to secure their success and anonymity. As a persistent detective, Sasagaki, continues to investigate the original murder case, the narrative explores themes of obsession, trauma, and the devastating consequences of a lost childhood. The series is a dark, psychological character study that examines whether two people can truly find redemption when their entire existence is built upon the destruction of others.