The route bus on which Totonou Kuno (Masaki Suda) got on to go to the museum was jacked. To the criminal who asks the passenger for his name, Sei asks the purpose and name of the bus jack. Then the criminal calls himself Inudo Otoya (Ryohei Abe), but he didn't tell him that he would understand the purpose.At that time, the investigation headquarters for serial murders stood at the Ohtonari police station. A new fourth body was discovered in the morning. The victims have nothing in common, and the suspect's eyes aren't even visible. While Nariaki Aoto (Michitaka Tsutsui) and Yuto Ikemoto (Matsuya Onoe) are busy, Seiko Furo (Sari Ito) is not allowed to participate in the investigation. At that time, Furo Hikaru was informed that her junior police officer had reported a bus jack. However, there are no problems with local buses and sightseeing buses. Bath light talks to Aoto and others, but she is dismissed as she is just a prank.The bus with the train stops at the park, and Otoya sends the passengers to the bathroom one by one. The first person to go to the bathroom thinks about how to contact the outside. Sei, who had been informed of the contact information by Ikemoto before leaving, wrote down the current situation on a memo paper and placed it in a place where the criminal could not find it.
When the bus starts running again, Sei makes Otoya angry. Otoya who went upside down was cut with a knife, but passenger Sho Kumada (Eita Nagayama) protected it. In addition, passenger Masao Sakamoto (Yuki Kubota) beats Otoya. The passengers are relieved, but Sakamoto points the fallen knife at the passengers ... After that, the bus arrives at a mansion at the direction of the criminal.

When Totonou Kuno (Masaki Suda) is enjoying making curry, he receives a call from Seiko Furo (Sari Ito) on his smartphone. She responded with an unpleasant premonition, and Yumitsu wants her to help solve the mystery of the incident. It is the identification of the bomb threat location posted on the dark site. The ciphertext of the alphabet is added to the notice, but police officers cannot clarify it. It was posted yesterday that it was set up in Shinagawa, but fortunately the building written in the notice was identified, so the bomb was discovered and the attempt ended. However, there was a notice again, and this time it was set up in the jurisdiction of the Ohtonari station, so Yuto Ikemoto (Matsuya Onoe) turned to Furo Hikari to ask for cooperation.At the reception of the bath light, I went to the interrogation room again. This is because the cooperation of investigations with civilians cannot be known to Nariaki Aoto (Michitaka Tsutsui) and others. Sei solves the mystery of yesterday's ciphertext. At that time, there is news that the second bomb was found. Sei is praised by Furo Hikari for his ability to break the code, but something gets caught. Meanwhile, the suspect was identified from the address posted on the dark site, and the suspect was interrogated but denied the crime. Ikemoto and Furo Hikaru are convinced that the suspect is almost black, but Aoto suspects that he is not wet because the address can be easily identified.The next day, the third notice was posted as Aoto was concerned. Sei who doesn't know such a thing goes out to eat in the rain. Then he was approached by a stranger (Tasuku Emoto). After having a conversation for a while, Sei finds out that the man has lost his memory.