The year is 1578. It is a time of strife and civil wars. During violent struggles for power, there were special soldiers who stood beside samurais. They sacrificed themselves in the line of duty, always at the service of their samurai masters. They operated incognito, wearing camouflage at all times. These spies were called "SHINOBI". They had once been united, but were now divided into countless antagonistic factions. Jin's group is targeted by another group... Riku is Jin's subordinate and the new leader of his group.