In the 1840s, Japan, as the Tokugawa Shogunate faces extinction, a corrupt lord named Matsudaira Naritsugu of Akashi freely rapes, tortures, and murders his own citizens. He is protected because the Shogun is his half-brother. However, the Justice Minister realizes the threat he poses if Naritsugu should further ascend, and hires a trusted older Samurai, Shinzaemon, to ambush and murder Naritsugu. Unfortunately, the conversation is overheard by the Samurai Hanbei, a childhood friend of Shinzaemon who has persisted in loyalty toward Naritsugu.
In late medieval Japan, Kai (Keanu Reeves) is a half-Japanese, half-English outcast who lives in the Akō Domain, which is ruled by the benevolent Lord Asano Naganori. When Kai was young, Asano found him lost in the forest and accepted him into his household. Kai and Asano's daughter, Mika, eventually fall in love despite Kai being scorned by her father's samurai due to his lowborn status and mixed ancestry.
A retired samurai must redeem himself for a crime that he committed earlier in his life. A squire is sent by the prime minister of Japan to keep watch over him.
Gonzo (Toshiro Mifune), a member of the Imperial Restoration Force, is being asked by the emperor to deliver official news to his home village of a New World Order. Wanting to pose as a military officer, he dons the Red Lion Mane of Office. Upon his return, his attempt to tell the village about a brand-new tax cut is quashed when the townfolk mistakenly assumes that he is there to rescue them from corrupt government officials. He learns that an evil magistrate has been swindling them for years. Now, he has to help the village, ward off Shogunate fanatics, along with the fact that he can't read his own proclamations.
After a plane crash in the Japanese mountains, its only survivor—a baby named Andrew—is adopted by a samurai master. Andrew, along with the samurai's son, Kenjiro, are trained in the warrior’s way. Andrew excels in his training and soon surpasses his stepbrother’s skills. Kenjiro's jealousy pushes him to join the Yakuza, where he takes the Mafia oath and forsakes the moral values of the samurai’s code. He leaves his father’s home, swearing to one day take revenge on his brother.
A group of travelers is stranded in a small country inn when the local river floods. As the bad weather continues, tensions rise amongst the travelers trapped at the inn. A traveling ronin (masterless samurai), Ihei Misawa takes it upon himself to cheer everyone up by arranging a splendid feast. Unfortunately he has no money and in order to pay for the feast he visits the local dojos and challenges the masters there for payment, termed in the film as prize fighting. Later, after breaking up a duel between two young retainers of the local clan he receives an offer of employment as a sword master from the local lord, Shigeaki. He has a tense interaction with the lord and his retainers, revealing his prowess at their expense.
Japon, 1863. Hachirō Kiyokawa bien que roturier est un redoutable bretteur, violent et connu pour sa proximité avec les nationalistes qui souhaitent le retour au pouvoir de l'empereur Kōmei au détriment du shogun Tokugawa. Aussi lorsque Hachirō Kiyokawa est relaxé du meurtre d'un policier et que le ministre du shogun lui confie la tâche de lever une milice (le Rōshi gumi) pour combattre les troubles à Kyoto, la cité impériale, au nom du shogun, amis comme ennemis s'interrogent sur les motivations de ce samouraï retors...
Le samouraï Sakunosuke Inui reçoit l'ordre du chambellan de son clan de tuer un autre samouraï, Sakuma Morie, le mari de sa propre sœur. Mais celle-ci est décidée à protéger son mari coûte que coûte...