Yoshie, the younger and ill-treated sister of a renowned Geisha, is discovered to have natural strength and fighting ability. She's recruited into an army of Geisha assassins by the rich and powerful owner of a steel-works, Kageno. During training large (and interesting) parts of their bodies are altered into weaponry directly linked to their brains. Yoshie soon realizes that Kagenos real plan is to have his robotic castle throw a new and very powerful nuclear bomb into the centre of Fuji-san, effectively destroying Japan entirely. With the help of other 'Kageno defectors', she sets out to stop him and his Tengu warriors.