Yabu’s treachery is exposed in the aftermath of the attack, turning his apparent service to Toranaga into a case for immediate punishment. Evidence links him both to Captain Sumiyori’s murder and to the attackers’ entry through a secret dungeon door. Toranaga orders him to commit seppuku before noon. Facing death, Yabu maintains his dignity, absolves his nephew Kasigi Omi, and appoints him heir; his death is later confirmed by the return of his head and the report that he died without assistance or a sound.

The Evidence Against Yabu

Toranaga begins by presenting Yabu as a vassal who has served him well, then directly asks why he killed Captain Sumiyori before the ninja attack. Yabu does not visibly react. Wearing his Yoshitomo sword, with his hand loose on its hilt, he asks who has accused him. Toranaga points to Kosami, a young samurai among the Browns, and calls him forward. The interrogation turns a private suspicion into a public accounting.

Kosami’s account establishes the first part of the case. Sumiyori had been exhausted after two days of duty. When Kosami returned to the room, Sumiyori was still lying in the futons, the room was undisturbed, and he had been stabbed once in the back. Kosami initially assumed the ninja were responsible and thought no more of it until Omi questioned him. The quiet, orderly room matters: the single wound and the absence of disturbance make the death a particular irregularity, not merely another casualty of the attack.

Omi then supplies evidence connecting Yabu to the attackers themselves. Two servants, he says, saw Yabu open the bolts of a secret door in the dungeon and heard him identify himself to the ninja with the words, “I am Kasigi Yabu.” The servants survived by hiding, while their testimony contradicts Yabu’s report that he retreated to raise the alarm after the attackers killed a man and nearly overran him. Omi explains that Toranaga had asked him to recheck the accounts and that this discrepancy demanded his attention. Yabu turns on his nephew, measuring the distance between them; when Yabu’s hand shifts, Sudara moves to shield Toranaga and Hiro-matsu raises his sword to Yabu’s neck. Toranaga orders them to hold.

Sentence and the Limits of Yabu’s Appeal

Asked by Hiro-matsu whether he committed the acts, Yabu denies them. Toranaga nevertheless declares that he believes Yabu did, forfeits his lands, and orders him to slit his belly that day, before noon. The sentence is final. Yabu’s own thoughts register the force of his position: the order is lawful, Toranaga is his liege lord, and the alternatives are execution or a dignified death. He accepts that Omi’s betrayal and the survival of two servants belong to his karma, even though the servants had been meant to die as part of the plan.

Yabu tries to redirect his death toward military service. He maintains that he is guiltless, calls Kosami mistaken and the servants liars, then offers to lead the charge down the Tokaido or take the first place in the first battle. Toranaga agrees that Yabu is his best general for the Musket Regiment, but says he does not trust him and repeats the order to die before noon. The exchange separates competence from loyalty: Yabu’s skill cannot undo the breach of trust or alter the sentence.

Omi, Izu, and Yabu’s Final Orders

Yabu responds not by attacking Omi but by formally absolving him of responsibility for the betrayal and appointing him heir. The gesture surprises Toranaga, who accepts that the appointment is wise. Yabu’s decision preserves a line of succession within his clan even as his own life and lands are forfeit. His composure in making the declaration is presented as an act of samurai honor and as the leader’s self-sacrifice, in contrast to the blinding temper he has to master.

He also tries to will Izu to Omi, treating it as a final favor. Toranaga refuses: Izu is no longer Yabu’s to give, since Yabu is his vassal and the province belongs to Toranaga to distribute as he chooses. Toranaga further insists that Yabu’s final orders remain subject to his approval and names Buntaro as the formal witness. When asked to choose a second, Yabu selects Omi. Omi bows and accepts the duty, his face colorless. The choice binds the nephew who exposed him to the ritual conclusion of Yabu’s sentence, even as Yabu has just protected Omi’s succession.

Death and Its Confirmation

Yabu obeys just before noon. Omi later brings his freshly washed, groomed head, mounted on the small pedestal customarily used for viewing. Toranaga inspects it as he has inspected enemies many times before, wondering what expression his own head might bear when viewed after death. Yabu’s face shows berserk wrath: lips drawn back in a ferocious challenge. Toranaga asks whether he died well. Omi reports that Hiro-matsu agrees with him: Yabu made two cuts, then a third in the throat, without assistance and without a sound.

The return of the head closes the gap between the order and its fulfillment, while the report gives the death a measure of dignity that the treason charge did not erase. Omi also presents Yabu’s will. When Toranaga asks whether Omi took off the head with one stroke, Omi confirms that he did and says he had asked Anjin-san’s permission to use Yabu’s sword. The sword thus remains present at the last stage of the event, but its use has passed from Yabu to the nephew who succeeds him. Yabu dies condemned by his lord, yet his final acts shape the clan’s succession and leave Toranaga—not Yabu—with authority over Izu.