The story is set in an alternate modern Japan in which 20th-century Japan's iconic Shinkansen high-speed bullet trains are also used as weapons of war and public transportation. There are two armed security agencies called "Air Self-Defense Force" and "Eastern Japan Railways" and they deploy security personnel that ride on the Shinkansen to patrol and protect the train lines from criminals and terrorists. Although they are supposed to work together, the two agencies' members don't get along very well and it is of utmost importance to cooperate well enough to ensure their common safety, especially since an incident happens in which the train had been derailed, resulting in 16 deaths and 230 more people had been injured. In response, the cabinet has decided to enhance the capability of the security staff and when push comes to shove, to assign security personnel who are highly-skilled and proficient in martial arts, those who can handle their weapons with confidence and reliability, the most impressive and dedicated among them all, on all 24 bullet trains, regardless of affiliation and identity. The show will center around the story of Takumi Ichinose, who's a rookie who has always dreamt of working for the high-speed train service, a dream that he'd been working hard for his entire life, and is happy as a clam to work as a security officer.