The rise to power of the famed Lady Kasuga no Tsubone, who established the 'Ooku' (the women's quarters at Edo castle) and acted as nursemaid to Tokugawa Iemitsu, the future 3rd Shogun is chronicled in this historical drama. Intrigue and suspicion abound as the two brothers Iemitsu and Tadanaga vie for the post of Shogun, while behind the scenes the remnants of the defeated Toyotomi faction, lead by Lord Ishida Mitsunari attempt to discredit the Tokugawa Shogunate and regain their former position as rulers of the nation. The hidden battles between Shogun Hidetada's wife and mistresses of the 'Ooku' come to light as they force the two brothers into a life or death struggle.
A new shogun is appointed to the throne when his brother dies. He find out that the former Shogun one of the women from his brothers harem became pregnant, but she escaped. The new Shogun would loose the throne if the child is a boy. Genshiro is doctor who, among other things, performs abortions, and is sheltering his love, another women who escaped from the harem. The new Shogun threatens to arrest the girl unless Genshiro hunts down the woman and aborts her child. Genshiro learns that the woman releases a "musky scent from her special area" when in ecstasy. Both Genshiro and his friend set out to find all the women of the former harem and have sex with them, by force if necessary.
