In 1995, a serial strangulation case occurred in Tokyo, five people were killed, and the murderer disappeared without a trace, and the case became an unsolved case. In 2017, when the case had long passed the effective period of litigation, a man named Masato Sonezaki (played by Tatsuya Fujiwara) published a confession book "I am a murderer", claiming that he was the murderer of the serial murder case 22 years ago, and mocked the incompetence of the police. This move shocked the entire Japanese society. Faced with the anger of the victims' families, the police were helpless. As the criminal police who investigated the case that year, Makimura Ko (played by Ito Hideaki) has never given up chasing the real murderer for many years. He was skeptical about Masato Sonezaki's words, and a fierce cat-and-mouse game unfolded between the two.