Ninja in the castle

Captain Sumiyori senses something wrong on the night watch; the red-spot ninja behind the audience-room spyhole watches him. Yabu, having bargained through Ishido's intermediary for Izu, the Anjin-san and the ship, kills Sumiyori and a Brown guard, opens the cellar door to the raiders and shouts "Ninjaaaaaa!" as the diversion. Blackthorne shoots the leader's brother, bars the inner door and fires through it twice while Kiri leads the women to Toranaga's secret iron-doored refuge. Chimmoko turns back alone with her knife and dies. Trapped, the women find their daggers taken; Mariko begs Blackthorne not to open the door: "they want me alive". He hammers a rusted battlement bolt loose as the ninja lays powder. "I, Toda Mariko, protest this shameful attack and by my death—" The blast kills her. The leader stabs Achiko, as paid for, and retreats with caltrops. Blackthorne, bleeding from the ears, blesses her body. Old Lady Etsu attests Ishido's treachery and steps off the battlement.

The ninja assault is written as a siege inside a room, and Clavell keeps the reader ahead of the victims by showing Yabu's bargain first. The bolted door is Mariko's argument made physical: open it and everything dies. Her death by explosion, unwitnessed, is the book's refusal of the clean seppuku.