Twins Tatara and Sarasa are born in a village ruled by the tyrannical Red King, one of the four kings among whom the Golden Emperor has carved up Japan, and a prophecy names Tatara as the child destined to free the country. When the Red King kills Tatara before he can fulfill it, Sarasa takes her brother's name and picks up his mission disguised as a boy, crossing a divided Japan to gather a rebellion behind the leader everyone believes Tatara to be.