Set in feudal Japan during the Edo period, a fragile peace is maintained at great cost. The chronicle follows Jubei Kibagami, a hired ninja who roams the countryside. At this time, ninja clans proliferate: the Hiruko Clan, bound to live and die in darkness, guards a sacred treasure known as the Dragon Stone, while the Kimon Clan, intent on restoring the power of the Toyotomi, seeks both the Dragon Stone and the treasure it conceals. Jubei Kibagami is the ideal protector of the Dragon Stone and of the only one who can wield it, the Light Maiden.