The game takes place in feudal Japan, introducing a pair of ninja: Rikimaru (力丸) and Ayame (彩女), members of the Azuma ninja clan since childhood. The two ninja serve the heroic Lord Gohda and work for him as his secret spies to root out corruption and gather intelligence in his province. However, the evil demonic sorcerer Lord Mei-Oh seeks to destroy Lord Gohda, and uses his demon warrior Onikage, who wreaks havoc throughout Lord Gohda's province.