Atsuhime - Season 1 Episode 40 Son Taking the Field

Saigo, who had been exiled, came back. At the gathering where Saigo and his old friends reunited, Tatewaki met a geisho, Okoto. The Chōshū domain, which is bent on regaining its political leverage in the capital, suddenly attacked the Imperial Palace. This is known as the Kinmon Incident. Tatewaki, who led the Satsuma forces, joined forces with the Shōgunate, along with Yoshinobu, and defeat the enemy forces. In the meantime, in Ōoku, Takiyama advised Tenshōin to let the Shogun have a concubine who could bear his heir, for she was purely concerned with the future of the Tokugawa clan and desired to consolidate the foundations of the Shugunate’s rule. Tenshōin, however, did not want to tear up the intimate relationship between Kazunomiya and Iemochi and flatly rejected the idea.