Former police officer, Terahara Ken, works for a private security firm. He is suddenly summoned back to Japan while on duty in Taiwan and ordered to protect Matsuoka Takanori, the secretary-general of the Democratic Party. At the same time, public prosecutor Sakurai Satoko, who was transferred to the Kochi District Public Prosecutors Office for a previous whistle-blowing incident, returns to the Special Investigation Department of the Tokyo District Public Prosecutors Office in a reshuffle by her former superior for the purpose of indicting a big shot. In the midst of this, a branch office of Tokyo Aoba Shinkin Bank is blown up and the bank's armored cash transport vehicle is robbed. The bomber who has set the events in motion is a young man called Aoyagi Tomoya. This incident creates a link between Terahara, Matsuoka, Satoko, and Ishikawa Aki, who works at Aoba Shinkin Bank.