In the year 1635, Hanshiro Tsugumo finds himself in a dire situation as his clan has fallen from grace. Seeking to regain his honor, he requests to perform seppuku in the courtyard of Lord Ii's castle. However, senior retainer Kageyu Saitō has a different story to share—one of Squire Motome Chijiiwa, a fellow samurai from the same clan who attempted a similar ritual the previous year, in 1634. Suspecting Motome was merely bluffing to gain money, Lord Ii's retainers hastily arranged the ceremony, with Hikokurō Omodaka serving as Motome's second.
Motome desperately pleaded for an additional day to secure 3 ryō to care for his ailing wife and child, but his plea fell on deaf ears. In a tragic turn of events, he attempted to take his life with a bamboo sword, only to find it breaking within him. The insistence from Omodaka to finish the act brought no solace, and it was soon Saitō himself who, in a moment of mercy, ended Motome's suffering by severing his head.
Despite Saitō's offer to dismiss his request for seppuku, Hanshiro remains resolute. He requests Omodaka to be his second, but fate has other plans as Omodaka, alongside Matsuzaki and Kawabe, are nowhere to be found. Hanshiro mournfully recounts the story of Motome’s father, Jinnai Chijiiwa, who was banished for unauthorized work on the castle and subsequently died, leaving Motome in the care of Hanshiro. Years later, when Motome married Hanshiro's daughter Miho and faced financial strain due to their sick infant son, he sold his sword to cover medical expenses. Ultimately, during a moment of despair, Motome's attempt at suicide bluff led to a tragic downfall, resulting in the death of his son and the heart-wrenching suicide of Miho, who used the very same broken bamboo sword after receiving her husband's body back along with the 3 ryō.
Fueled by rage and disgust over the cruel fate that befell Motome due to the inaction of Omodaka, Matsuzaki, and Kawabe, Hanshiro sought vengeance by hunting them down and humiliating them by cutting off their chonmage topknots, a disgrace that forced them into hiding. In a powerful act of defiance, Hanshiro returns the 3 ryō to Saitō and challenges the other samurai to a duel with a bamboo sword, showcasing his prowess and determination. He boldly declares that a warrior's honor is not merely an ornament, knocking over a decorative suit of armor as a statement. In a final act of collective shame, Omodaka, Matsuzaki, and Kawabe choose to commit seppuku. As the tension in the courtyard dissipates, the remaining retainers gather to restore the suit of armor to its former glory. When Lord Ii reenters the castle, he inquires whether the suit has been polished, representing the enduring pride and honor of the castle.
