S1·E26 A Hell-Raising Petition

While the dispute over shogun's successor heats up, Ii Naosuke, siding with the Kishu-Tokugawa family that pushes Yoshitomi to become shogun, visits Honjuin to ally with her. Atsu-hime, under Nariakira's order to make Yoshinobu the next shogun, is driven into a corner. Nariakira submits an official statement declaring his position on the next shogun to the Tokugawa shogunate, which stirs the shogunate including "Ooku.