The setting is the twilight years of Shogun rule. The main character is a passionate youth named Hiwou who embarks on a journey in search of his lost father. Accompanied by his friends, Hiwou and his gang encounter many bumps in the road along the way in this animated adventure story that is a fusion of Japanese history and mechanical robot action. It is a story of good vs. evil as Hiwou & friends encounter the evil Fujin, who use wind-up dolls for war to gain power.

This is an original work by the BONES Production Company whose other titles include Fullmetal Alchemist, Cowboy Bebop, Scrapped Princess, and Wolf’s Rain.
BONES created this story by integrating Samurai themes with mechanical wind-up dolls.