The lord of the Oshi fief is killed by his trespassing neighbour, the cruel and despotic Nariatsu, son of the former Shogun. After an investigation, the Oshi clan is blamed for what happened and sentenced to be disbanded. Eleven of the best samurai of the clan refuse the sentence and are willing to give their life for justice.
A cynical samurai is left as the sole survivor to fulfill a plot to assassinate the puppet of a villain intent on usurping the shogunate in the 17th century. A Shogunate Elder connives to rule Japan by making his puppet, the Shogun's brother Tsunashige, the next Shogun. The best strategist in Japan, Yamaga, leads a plot to stop the Elder, but his cabal is betrayed and most of the conspirators are captured and tortured.
An innocuous comment during a weapon inspection wounds the pride of low-ranking samurai Shinpachi, leading to an argument with his superior. The situation snowballs out of control, leading to a deadly duel and political fallout which threatens the entire clan. Declared mentally unstable by the corrupt authority, Shinpachi begins his descent into true insanity…
