On June 24, 1989, 21 people, among them children, were found poisoned to death in the elementary school of Otousu village in Hokkaido. Bungo Sano, a police officer of the same village, was arrested. Twenty eight years later, Sano’s son, Shin Tamura, starts to suspect that his father, who continues to plead his innocence even after being handed the death penalty, may have been wrongfully convicted, and launches his own investigation. Upon arriving at the crime scene, a thick fog descends, engulfing Shin, and he finds that he has slipped back in time to the year 1989. The curtain rises on this authentic crime suspense that transcends time and space in a confrontation with the truth.