The movie, set in the mid 1600's, opens with some ladies bathing a young lord who is guarded by some samurai. All of a sudden there is an attack by ninja archers. They then attack with swords and try finish off the job but some warriors appear to protect the Shogun's young heir. One of the Shogun's vassals. Lord Abe, wants to have his the heir's younger brother replace the Shogun instead. Igo Gyobu (Ken Ogata) has been hired to protect young Master Takechiyo.
Mater Takechiyo has been ordered by the Shogun to attend a ceremony at Edo. If he does not go he will be punished and his brother will become heir. Even though they know it is a trap they must go. It seems that ten years ago Lord Abe had sent his sister, who was married to Gyobu to become a mistress for the Shogun. Gyobu tried to kill Lord Abe and still hates him.
Ninja's led by Shozaemon Iba (Sonny Chiba) attack again. He duels with Hotta, who is protecting Takechiyo. and kills him. Takechiyo with Gyobu and his guards manages to escape. Iba hunts and Gyobu protects, as the groups make their way towards Edo. One of Gyobu's men wants to leave, saying that they had done enough for what they had been payed, but Gyobu pushes on.
Takechiyo asks if it is his father who is trying to kill him. Gyobu says that it is possible. One of the ladies travelling with Takechiyo says that it is true. She says that the Shogun hates him because he doesn't look like him. He favors his younger brother. Tokumatsu, instead. They give the boy the choice and he decides to confront his father, not escape from him.
Fighting overwhelming numbers, Gyobu and his small pack of men hold off the Shogun's army. When confronted with overwhelming numbers, Gyobu challenges Lord Abe to a duel and ends up getting his revenge. In the fight that follows one of Gyobu's men lights himself on fire and then attacks a group of soldiers and and the boy escapes again. Gyubu is surrounded by soldiers. and though it is not shown, we are led to believe he has met his end.
Takechiyo makes it to Edo and his father is furious. He tells his consort to get rid of him and she brings him poison and tells him that it is from the Shogun. He goes to drink it but his companion lady stops him. Takechiyo then comes before his drunken and sick father. The Shogun goes to slash his son, but his lady gets in front and takes the blow. She then stabs him as her last act on earth, killing him.
Really good action scenes directed by Sonny Chiba in a pretty good samurai movie.