Blackthorne and Mariko reach Yedo under escort. At the wharf, Blackthorne glimpses the Erasmus—freshly refit, guarded, and immaculate—stoking his urgency to inspect her and reunite with his crew. They proceed to the castle as protocol allows only a brief detour.

On the road and at inns, Mariko had calmed Blackthorne after a bitter rupture with Father Alvito. One dawn, Gyoko approaches Mariko with three secrets: Onoshi’s confessional betrayal against a fellow Christian daimyo; Omi’s plot against Yabu overheard by a cook; and Zataki’s lust for Ochiba and frictions with Ishido. Gyoko seeks two swords for her son in exchange. Mariko presents this to Toranaga, who, outwardly morose, rejects elevating Gyoko’s son and banishes Gyoko and Kiku to an inn, yet listens carefully.

In audience, Buntaro begs permission to take Blackthorne’s head; Toranaga defers the killing until after Buntaro serves as his second and orders Mariko to depart for Osaka in three days to prepare his way. Toranaga privately sends Buntaro at dawn via Takato, with a written dispatch solely for Toranaga’s mother, warning he must deliver it or die destroying it.

Alone, Toranaga exults: Gyoko’s intelligence promises a reprieve if true. He reasons that Zataki covets Ochiba and resents Ishido, and that Kiyama or Onoshi can be turned. While still acting defeated to all, he refines his Legacy, drafts a secret offer—proposing Zataki marry Ochiba, granting him Christian domains after purges, safe passage through Shinano, and a joint strike under Toranaga—and dispatches a pigeon to secure Buntaro’s passage, signing as Minowara for the first time.

At home, Mariko contemplates suicide over shame and peril. Buntaro arrives, railing at Toranaga’s weakness; their quarrel explodes, he shatters his sword against a beam, and storms out vowing to settle matters in Osaka. Mariko composes herself.

Summoned, Blackthorne meets Toranaga, who grants him a night visit to his crew and an inspection of the Erasmus tomorrow, and promises two hundred samurai vassals. Privately, Blackthorne urges seizing the Portuguese Black Ship to pressure Christian daimyos; Toranaga refuses open war, maintaining the Osaka route. Blackthorne then secretly petitions for Mariko’s divorce; Toranaga forbids any mention to her or Buntaro but will consider it. Mariko and Blackthorne leave the castle separately, agreeing to meet again tomorrow.