 Various nations and organizations around the world train and utilize Contractors as spies and assassins, resulting in violent battles for valuable objects and information.Following the disastrous Heaven's War, the United States lost its dominant position as a superpower to a mysterious organization named the Syndicate.The story revolves around a Chinese contractor codenamed "Hei" as he undertakes various espionage and assassination missions in Tokyo under the direction of the aforementioned Syndicate.