Des paysans décident de se révolter contre le seigneur local en kidnappant sa fille, ils souhaitent que leur ras-le-bol se fasse enfin entendre aux yeux de cet homme qui se complait dans sa riche situation sans se poser des questions. La famine n'est pas son problème. Mais un rōnin de passage fait irruption chez les révoltés, Sakon Shiba est simplement porté par sa curiosité. Il ne peut que se joindre à ces hommes méprisés mais faibles face à la force d'un Seigneur. Le rōnin parvient vite à ramener un autre rōnin, d'une condition pauvre au point qu'il préfère coucher en prison. Le trio se complète par le garde du corps du Seigneur, qui comprend que son statut d'homme de sabre l'empêche de se prélasser dans une vie stable et calme. Et pendant les trois hommes unissent leurs forces pour affirmer la parole des paysans, ces derniers restent passifs et effrayés, ils sont enfermés dans la peur de mourir.
The film tells the story of two Shinsengumi samurai. One of them is Saitō Hajime (played by Kōichi Satō), a heartless killer and the other is Yoshimura Kanichiro (played by Kiichi Nakai), who appears to be a money-grubbing and emotional swordsman from the northern area known as Nambu Morioka. The main storyline is set during the fall of the Tokugawa shogunate, but it is told in a series of flashbacks as two characters reminisce. The themes include conflicting loyalty to the clan, lord, and family.
In 1945, Logan is held in a Japanese POW camp near Nagasaki. During the atomic bombing of Nagasaki, Logan rescues an officer named Ichirō Yashida and shields him from the blast.
Attacked and wounded by a group of traitorous Japanese ninja, a mercenary samurai named Yamada (Ozeki) is rescued and nursed back to health by a group of Siamese warriors, in service to the King of Ayothaya. Confused by the mysterious identity of his assailants, Yamada stays with the warriors, befriending them, learning their art, and eventually pledging his loyalty and life to their cause and kingdom.
The film's plot follows a traditional theme, with Zatoichi (a blind swordsman) coming to the defense of townspeople caught up in a local Yakuza gang war and being forced to pay excessive amounts of protection money. Meanwhile, Zatoichi befriends a local farmer and her gambler nephew and eventually offers his assistance to two geisha siblings (one of whom is actually a man) who are seeking revenge for the murder of their parents. The siblings are the only survivors of a robbery and massacre that was carried out on their family estate ten years ago. They soon discover the people responsible for the murders are the same Yakuza wreaking havoc on the small town.
The films starts with young Ichi's wife (Satomi Ishihara) being murdered by Toraji (Sosuke Takaoka), the cowardly art loving son of a yakuza boss. Following her death, Ichi (Shingo Katori) returns to his hometown, where he hopes to resume a normal life under the guise of farmer with his friend Ryuji (Takashi Sorimachi). However, the same group of yakuza plan to change Ichi's hometown into a harbor, and start exploiting local peasants for money. Ryuji's land deeds are taken and ransomed at a high price, so Ichi uses his gambling skills to win the money for the deeds. This unveils his identity as the infamous Zato Ichi which the Yakuza don't like and burn down the house. The villagers draft a Tanran scroll to present to a passing official asking for assistance. However having Zato Ichi, a wanted criminal, in the village would not work in their favor so they devise a plan to dispose of him. They give him a blank scroll to "deliver" to the officials and lead him on a dangerous path sending the yakuza after him. However, he realizes it is the wrong path and makes it to the officials. His betrayal is revealed when he shows the blank scroll to the officials and they are insulted and leave. Ichi takes the responsibility of getting rid of the yakuza on himself, going to the yakuza headquarters and killing the boss. However he is shot by Toraji and stabbed by one of the Yakuza minions. Crawling on hands and feet he goes to the beach where he presumably dies reuniting with his wife in the next life.
Following their lord being forced to commit ritual suicide, forty-seven samurai warriors await the chance to avenge their master and reclaim their honor.