An entire village has been wiped out by a mysterious plague and an anti-government conspiracy of invulnerable demons seems to be responsible. A wandering ninja, Jubei, is recruited by an old man to fight eight demons as well as a man that the swordsman thought he had slain years ago. The two are also joined by their female counterpart, Kagero, to team up to defeat the plotters. Jubei is a classic reluctant hero, agreeing to participate in the mission only after being fed a slow-acting poison; the antidote will be supplied after he cooperates. And Kagero, a looker whose embrace is lethal, is a femme fatale with a difference that seems distinctively Japanese, her body is too toxic for any intimate contact especially for a warrior with a pure-soul.