Set along a backdrop of a fictitious second world war at an international city in Asia. In Japan, Lieutenant Colonel Yuki recommends the creation of spy training school `D Kikan`. Meanwhile, Kato is facing capital punishment for his refusal to follow a superior‘s order. Kato is then scouted by `D Kikan`. He goes through a harsh training regiment and faces his first mission as a spy. In order to seize American ambassador Graham‘s confidential documents `Black Note.` Kato infiltrates into an international city. A battle to gain possession of the `Black Note` ensues between Kato, a mysterious woman named Rin, the British Spy Agency, the Soviet Spy Agency and the radical army in Japan.
