During the Edo period , under the rule of Tokugawa Tsunayoshi , people began to enjoy prosperity. However, amidst this, Mito Mitsukuni, wanting to experience the bloody excitement of the Sengoku period, traveled around the country, causing trouble on his travels and enjoying himself. Several of his retainers died, and the Mito domain , concerned by the successive deaths of its vassals, decided to recruit retainers from among the ronin . Inoue Shinnosuke, an unsuspecting ronin, applied for the position, seeing it as an opportunity to serve the Mito domain, and was accepted, but he ended up becoming embroiled in Mitsukuni's actions.