An unpopular back alley. Minoru Sakashita (Nozomu Kotaki) gives cash to a suspicious man Komuro (Hideaki Washio). Komuro counts the money and laughs fearlessly...
On the other hand, the new full-time investigative team receives news that police chief Masatake Yamagishi (Shingo Tsurumi), who works at the police box, has been shot. Yu Amagi (Kiyuki Higashiyama) and other members of the new full-time investigative team head to the crime scene, where they find the dead body of Yamagishi, who has been holding onto a traffic sign for some reason after fighting with the criminal. After a while, the first investigative section chief and the members of the first section appear on the scene. Surprisingly, there is a high possibility that the bullets found in the bodies were of the same type as the guns used by the Metropolitan Police Department, and the police killed the police officers!?
　Following investigation by the First Investigative Division, the bullet used in the crime matched the one used by the police officer who was shot dead in the Hachioji police murder incident 12 years ago. According to Koshimizu Yuuto (Yuge Tomohisa) of Higashi-Hachioji Police Station, who is continuing the investigation, Furuichi Jun (Akagi Yo), a high school student at the time, was found shoplifting at a supermarket. It is believed he was shot and killed. There was also a theory that he had undergone plastic surgery and escaped, but he has not been caught until now, and if the murder weapon was used at that time, could it be Furuichi, who has gone into hiding? In the midst of this, Michitoshi returns home on time, despite the fact that a police officer was killed in a big case that is also connected to an unsolved case 12 years ago. At that figure, Amagi was staring at him quizzically...
Later, Amagi and Takumi Nonomura (Jin Shirasu) interview Kazuhiko Doi (Shunya Toyama), a cleaning staff member at the scene where Yamagishi was murdered. According to Doi, about a month ago, Yamagishi had a dispute with an elderly homeless man. Also, according to a junior former police officer, Yamagishi had a bad work attitude and was asked for money at times, but the reason why he became rotten was that he missed Furuichi, who was on the run. He says that's what caused it. In addition, there were rumors that he received money from Furuichi and deliberately overlooked it.
And then, Amagi finally followed Michitoshi, who returned home on time as usual. Then, where Michitoshi is headed, Amagi encounters an unexpected scene. Before long, Amagi learns of Michitoshi's hidden past...