Zatoichi and the Chess Expert

Jumonji killed Roppei because Roppei was the only person who could identify the man who murdered the siblings' father. By eliminating Roppei, Jumonji removed the sole witness who could connect him to the original killing, allowing him to escape accountability for his earlier crime.

Earlier, it was established that Roppei was the only one who could identify the killer during a heated game of shogi, making him a threat to Jumonji's secret.

A fishing float was discovered at the scene where Roppei was strangled with wire. This physical evidence directly linked Jumonji to the murder, as the float was a piece of equipment consistent with his background as a fisherman.

The film hints at Jumonji's connection to fishing throughout his characterization, making the discovery of the float a crucial piece of evidence.

Zatoichi chose not to kill Jumonji despite clearly defeating him in their duel. Though Jumonji was guilty of two murders, Ichi showed restraint, perhaps seeing enough of his former friend's humanity during their shogi games to stay his blade. He left the vengeance to Sasagara and Kume instead.

The three shogi games between them showed mutual respect, with Zatoichi observing Jumonji's character closely rather than rushing to judgment.

Sasagara and Kume revealed that their father's killer had a distinctive quirk: he would rub his nose and snap his fingers. When Zatoichi observed Jumonji exhibiting this exact behavior during their interactions, he became certain of his guilt in both the father's murder and Roppei's killing.

This detail was introduced early in the investigation, waiting for Zatoichi to match the behavior to a suspect.

Zatoichi revealed that he once loved a woman named Otane who is now dead. When Otane (Miki's aunt) confessed her feelings for him, Ichi remained silent about his own unresolved emotions, as he still harbored feelings for his departed love who shared the same name.

This backstory explains Zatoichi's emotional distance and silence during Otane's confession, adding depth to his character.

The shogi games served as a psychological battleground where Zatoichi studied Jumonji's mind and patterns. While Jumonji won two of their three games, Ichi used this observational time to confirm his suspicions about Jumonji's guilt through his behavior and reactions, making the games a tool for investigation rather than mere recreation.

The very first encounter between them on the boat established their mutual respect and rivalry through the game.

When Miki was accidentally injured during the revenge attack by the dice cheaters, Zatoichi felt responsible for her welfare. He navigated dangerous situations and bargained fiercely to procure the medicine needed to cure her serious injury, demonstrating his deep sense of protectiveness toward Otane's family.

The incident showed Zatoichi's willingness to go to great lengths to protect innocent people, setting up his later protective role.

Sasagara and Kume bowed to Zatoichi as a sign of respect for his role in exposing Jumonji as their father's killer and his decision to let them take vengeance. Despite his wandering samurai nature, they recognized his honor and the justice he provided, even though he chose not to kill Jumonji himself.

Their bowing acknowledged Zatoichi's integrity and the complicated nature of his justice, which they seemed to understand.

When Miki called out to thank Zatoichi as he walked away, he softly replied 'arigato', returning her earlier gratitude. This tender moment contrasts sharply with the violence of the duel, showing the human side of the wandering swordsman. It underscores the bittersweet tone of the film, as Ichi carries the warmth of her gratitude into his solitary life.

Miki's sincere thanks earlier in the film had visibly moved Zatoichi, making this return of gratitude emotionally resonant.

Zatoichi remained silent about his past love for a woman named Otane when Otane (the aunt) confessed her feelings because he was still emotionally connected to his departed love who shared the same name. His unresolved grief made it impossible for him to reciprocate her feelings, and he chose silence rather than explain his complicated emotional state.

This backstory was revealed at a critical emotional moment, adding depth to Zatoichi's characteristic stoicism.

After arriving on Honshu, a group of men who had tried to cheat Zatoichi at dice attempted to take revenge on him. Zatoichi swiftly defeated them in a brutal but controlled confrontation, turning the tables on his would-be attackers and leaving them defeated.

This early display of his fighting prowess set the tone for his capabilities throughout the film.