Musashi walks alone from the mountains to the seashore, then to the farm fields, "in search of knowledge and to complete his character as a respectable samurai". It is evening as he stops by a hut and prepares a bandana on his forehead. He tells a young lad to go, the boy knows Musashi is there to duel with Old Baiken. Shisido Baiken arrives with two aides.The two men face off, Musashi with his katana, Baiken with rapidly swinging ball and chain and scythe (kusarigama). After a tense battle Musashi delivers a killing thrust. An old man passing by chastises Musashi, although he is skilled fencer he lacks chivalry, is not mentally relaxed, is not a true samurai.
The boy, Jotaro, follows Musashi on his journey. He is an orphan. In Kyoto, Otsu still waits, selling fans by the bridge. Akemi comes by and notices her sadness, they talk, Akemi says she longs for a certain man also. Toji, comes and grabs Akemi to take her back to entertain Seijuro Yoshioka, a wealthy Martial Arts School owner. Toji and Oko discuss how rich they will be by pimping out Akemi. Matahachi still hangs around the house also and sings a mournful song.
At the Yoshioko school Musashi practices with the students, laying a beating on them one by one. He's killed two already and finally Musashi demands a match with the school master, Seijuro. Later Seijuro arrives to see his wounded students, defeated by who they consider a back country fencer. Seijuro prepares for a duel but is stopped by Toji, who says Musashi is not good enough for the master. The men whisper and plan. They attack his room in mass but Musashi is gone. He left a note saying Seijuro is to post his time and place for a duel by Sanjuro Bridge the next day.
Back at the house, Oko and Toji try to cheer up a pensive Seijuro. Akemi delivers tea. Toji tells him to have his brother Denschichiro fight instead. Akemi sees Musashi's note and his signature, realizing it must be her Takezo. She goes to tell a stunned Matahachi, who sets out to find his old friend.
In a shop Musashi is trying to get his sword sharpened, the smithy calls Musashi a murderer and refuses to polish the weapon. The samurai leaves in anger, then pauses, returns and asks humbly, the smithy now agrees but says only the Master Koetsu Honami can polish the sword. At Honami's shop the master polisher is friendly and shows a recent job, a long sword nicknamed "the Clothes Pole". Musashi is interested in the owner and learns it is a Kojiro Sasaki.
In a park Matahachi walks nervously. He sees a group of men attack a samurai, they cry out they made a mistake. The dying man gives Matahachi a package to deliver to Kojiro Sasaki.
At the house Seijuro punishes Akemi for loving his enemy, he rapes her. Oko and Toji leave them alone. Afterwards, Akemi glares at her mother with hate.
In the dusk Musashi waits by the bridge. Otsu arrives by coincidence and the two meet once again, Otsu never wants to leave him again. A stoic Musashi admits he prefers his sword. Suddenly a large group of men approach. Vastly outnumbered, Musashi fights and retreats, demanding a fair duel, he escapes by the riverbank.
A tall young samurai crosses the bridge and speaks to Toji. Toji acts bossy until the young man suddenly takes his sword and quickly slices off Toji's topknot with the "Swallow Turn" move. The samurai strides away back across the bridge.
Otsu runs along the river calling for Takezo. Akemi is there also and hears her. The two women meet and Akemi realizes they both long for the same man. She lies to Otsu that Takezo had proposed to her. Sadly Akemi says she was going to kill herself but now will live for Takezo. Otsu weeps, not believing it.
Back at the temple she seeks guidance from Takuan the Buddhist priest. She wants to be nun. Takuan tells her she doesn't have to and introduces her to Jotaro.
Akemi wakens at Sasaki's house. Startled, he tells her she is free to go but asks her to stay awhile. He grills her about Musashi. Toji and a group arrives to take Akemi back, but Sasaki threatens them with his long sword. In a clearing the men surround him, he strikes down two until one man stops the fight, finally recognizing him.
Elsewhere in Kyoto, Koetsu Honami has taken Musashi to see the star courtesan Yoshino at the best nightclub in town. She performs her dance routine then comes to sit by Musashi. An ascetic, Musashi declines any drinks, the women make ribald double entendres.
At the school Denschichiro comes to see his older brother, ripping him for the cowardice in not fighting the previous evening. All over town the men are looking for Musashi. Homani's mother tells Takuan Musashi is being kept occupied in the geisha quarters until the trouble passes. Finally two men discover where he is and deliver a summons from Denschichiro to duel at nine that night at Rengein Temple.
At the temple Denschichiro waits as Musashi arrives. The two men commence to swordfight. As a geisha sings, Musashi returns none the worse for wear, the geisha tells him he must visit with Lady Yoshino. Mushashi is shy beside the aggressive courtesan, she taunts him and questions his attitude towards women.
Seijuro sees his dead brother laid out and tells him he shouldn't have been so rash. He tells Sasaki he must now fight Musashi. Seijuro then goes to a bedroom and apologizes to a sad Akemi and asks for one kind word from her to help his spirit, she refuses and says she'll pray for Musashi.
Toji has 200 gold pieces and prepares to leave town with Oko, leaving Akemi behind. As the two run out they bump into Matahachi and scurry off. As Matahachi gets up his mother Osugi arrives. He shows his mother the scroll he took from the dying samurai, it is a diploma from the Chujo School and he claims it as his, and he has changed his name to Kojiro Sasaki.
At Yoshino's Musashi relaxes by painting, he hears the word on the streets is he's a coward. Yoshino leaves him a farewell note, not being able to tell him goodbye, he is her one true love. Now he walks through a deserted part of town. Again he is quickly surrounded. Sasaki intervenes and introduces himself to Musashi. They agree to a duel with Seijuro at five the next morning at Ichijoji Temple, 19 February. The duel is posted for all to read.
Otsu prays at the temple, Takuan prepares to have her long hair cut to become a nun. As Takuan readies the razor Jotaro comes and tells her she must go the the Ichijoji Temple for the duel.
Musashi cleanses himself by a well. In the dawn a large group of men confront an approaching man, it is Sasaki, coming to be a witness. They tell him he is a meddler and he realizes they are to ambush Musashi, the house of Yoshioka has no honour. Sasaki retreats.
Osugi has convinced Matahachi to kill Otsu, they intercept her in the woods. Matahachi instead wants to elope, Otsu explains she loves Takezo. Enraged, Matahachi chases her with the long sword. Sasaki happens to come by. Boldly, Matahachi proclaims himself as Sasaki. The real Sasaki is amused and introduces himself.
Musashi stops briefly at a well and ponders the enscription. Akemi arrives and hugs him. Otsu also shows up and sees the two in a close embrace. Akemi tells him there are 80 men waiting for him, she tells him not to go. Otsu watches as Musashi pushes Akemi down and continues towards the duel.
He strides confidently through the bush and arrives behind the ambushers. He decides to go in as promised, demanding to see Seijuro. Defiant, he draws his blade and starts taking them down. Otsu arrives as more reinforcements also appear. Musahsi continues to kill his attackers. Sasaki and Akemi watch from a hillside nearby. Archers land their arrows at Musashi`s feet. He retreats slowly across a rice paddy, the thick mud and water hampers the mob. He gets to dry land first and makes an escape.
As day breaks Takuan appears. Otsu announces she will not be a nun afte rall.
Somewhere in the woods Seijuro confronts a tired Musashi. He claims he is not a coward but his men stopped him earlier. The two men draw and approach, Seijuro is nervous, he falls to the ground and Musashi has him at his mercy. Recalling the old man`s earlier words about chivalry, Musashi relents and leaves Seijuro alive.
On the run, Mushashi is exhausted and collapses at a stream. Jotaro sees him and calls for Otsu. Later, by a mountain stream Musashi awakens. Otsu is happily washing clothes by the water. The two are living their dreams. Overcome with emotion, Musashi wants to consummate their relationship right there, but Otsu is not ready to go all the way. Confused, Musashi quickly packs his swords and leaves, he renounces the love of women. High above, Sasaki sees him walking alone and wishes him luck in his development.