AIBOU

Somewhere a television presenter is murdered. Somewhere else, a member of the Japanese Diet (parliament) is saved from almost-certain death by two policemen assigned to her detail. The police soon identify a connection between the cases and also find it part of a larger picture. The cases soon hit close to home.

Hostage cases are scarce. Even more scarce are they in Japan. Even further scarce are hostage cases in Japan where the confined are the police themselves. The head of the police and his officers are held in a conference room at the headquarters. The room is surrounded but the perpetrators and their motives are a mystery. The matter becomes even more surprising when the hostage taker is revealed as a former policeman.

Detective Kenichi Itami from the The National Police Agency and Akira Iwatsuki from the cyber investigation team investigate a complex murder case. The victim was under investigation by the cyber investigation team. As Detective Kenichi Itami and Akira Iwatsuki delve deeper into the case, pressure from around makes their investigation even more difficult. Secretly, a national financial doomsday scenario is carried out under the plan of "X Day".

A crime syndicate shows the girl who was kidnapped 7 years ago is still alive and demands 900 million yen as a ransom. Ukyo and Wataru realize that the group has a deadly poison and real hostages are 500 thousand Japanese people.

A news report circulates about a man who died after being kicked by a horse on a small island located 300km away from Tokyo. National Police Agency director Takeru Kanbe assigns Vice Director Mineaki Kai the task of making sure rumors surrounding the incident are fully investigated. Soon, partners Ukyo Sugishita and Tooru Kai are dispatched to the island to conduct the investigation. When Ukyo and Tooru arrive on the island, which is privately owned by a wealthy businessman, they discover a unit of former Self-Defense Forces personnel who have set up a small community as they participate in training exercises. While Ukyo initially expected to be investigating an accidental death, he quickly becomes convinced it was actually murder. However, when they finally manage to uncover conclusive evidence of this, the soldiers attack.