On a boat trip to Honshu island, Zatoichi (Katsu) makes the acquaintance of Jumonji (Narita), an expert shogi (Japanese chess) player and swordsman. Once on Honshu, a group of men that had tried to cheat Zatoichi at dice try to take revenge upon him- only for Ichi to turn the tables on them in the tussle. However, Miki, the niece of a woman named Otane, is injured in the confusion, compelling Ichi to go to great lengths to procure the medicine needed to cure her injury. When she recovers, the child sincerely thanks him, leaving him overwrought with emotion.
Traveling on the road, Zatoichi (Katsu) encounters a dying man who gives him a bag full of money and the name "Taichi". Traveling on, he makes the acquaintance of a blind biwa-playing priest. The two travel to a town that is having their annual thunder drum festival. The town is under the domination of a Yakuza boss who extorts from the people.
Le seigneur de guerre Oda Nobunaga vainc rapidement ses ennemis dans sa quête de pacifier et d'unifier le pays sous son autorité. Il existe cependant une région que lui-même craint : la province d'Iga où vivent les ninja de l'école Iga-ryū, connus pour posséder des armes de guerre extraordinaires, ne pas penser comme des humains et assassiner pour de l'argent. L'un de ses ninjas, Mumon, reconnu comme un assassin exceptionnel et qui n'a pas d'égal au combat, a gagné le surnom de « ninja le plus fort d'Iga ». Il est cependant également paresseux et cherche seulement à gagner de l'argent pour plaire à sa femme, Okuni. Dans le même temps, un ninja nommé Heibee Shimoyama devient désabusé par la manière de vivre de son peuple.
Un samouraï du nom de Daiemon qui détenait le record du nombre de flèches tirées sur une cible en une journée avec 6200 flèches, lors du tournoi annuel qui se déroule au temple Sanjūsangen-dō de Kyoto, est détrôné l'année suivante par Kanzaemon Hoshino qui parvient à toucher 8000 fois la cible. Un panneau au nom de sa famille célébrant l'événement est apposé sur le temple en remplacement de celui de Daiemon, apportant un grand prestige à la famille Hoshino. Lors du concours suivant, Daiemon échoue à retrouver son bien avec « seulement » 7300 flèches ayant touché la cible et se suicide par seppuku.
Seeking to atone for his violent past, Zatoichi (Katsu) embarks on a pilgrimage to visit the 88 shrines on Shikoku. On the road, a man (Igawa) attacks Zatoichi but is killed by him. Zatoichi follows the man's horse back to his home.
In a rural village, Zatoichi (Katsu) encounters Shushi Ohara (Suzuki; modeled after 18th-century agriculturalist Yagaku Ohara) a sword-less ronin who defends himself against multiple attackers without killing them. Ohara leads a peasant movement advocating the abstention from gambling, drinking, and whoring.
Zatoichi (Katsu) checks into an inn where he shares a room with an ill woman and her young son named Ryota. Before the woman dies, she requests that Zatoichi take her son to his father, an artist living in the nearby town of Maebara.
Zatoichi comes to a village which is the local hub of family farms in a silk growing region. The most prominent villager is Matsugoro who apparently will stop at nothing to bring all under his control. The small village does have a kind doctor, Dr. Junan, who lives with his daughter Oshizu.
Zatoichi's travels have finally brought him back to the village where he was trained in the arts of the masseur, nearly ten years ago by his old sensei, Master Hikonoichi. His proximity to his former teacher compels him to pay a visit, only to learn that Hikonoichi was recently killed while traveling, and his daughter Sayo has been sold into prostitution to repay the money lent to her father by local business man Tatsugoro. Zatoichi sets out to free Sayo, only to discover that the entire village is suffering -- victims of a scheme that has either forced their daughters into prostitution, or into doing the bidding of Tatsugoro, who is working for the corrupt Intendant, Isoda. Sayo provides him with the toggle of a medicine pouch, recovered from her father's hand.
Many years ago ronin killed parents of the young girl named O-kin, and crippled her by cut off her right arm and gouged out her right eye. Nevertheless, this girl grew up and became a great swordswoman. Despite her mutilated body, she is unbeatable. Now, she lives in the small town and owns a very valuable and rare sword - The Drenched Swallow. O-kin protects from robbers and ronin a little girl and her grandfather. Local Daimyo collects swords and orders to samurai takes away all swords from its owners. A few samurai came to girl's home and kill her grandfather before were killed by O-kin. Now O-kin wants to take revenge. Together with another swordsman and simultaneously heavy sake drinker, O-kin protects the child.