This film tells the story of the protagonist of the county police propaganda class who independently investigates the mystery of his friend's mysterious death, uncovers the truth of the incident, and gradually reveals the story of the "public security police" who have emerged. The female college student living in Pingjing City, Aichi County was killed by the eldest son of the shrine after being harassed by stalkers for many times. According to an exclusive report from the local newspaper, the police delayed accepting the report of a female college student and went on a trip to comfort them during this period. Morikuchi Quan, a staff member of the county police propaganda and listening class, suspected that newspaper reporter Tsumura Chika had broken his promise to report, but Chika, who wanted to prove his innocence, was found dead a week later. The thoughts of self blame and regret drove Quan, vowing to personally catch the murderer who killed Qianjia.