Mukitsu was a doshin of the village of Aian, in the Naishou Province. The headman Shidou, his wife, and his daughter all disappeared together. On the same night, a blacksmithy worker was murdered. The local samurai, Matsu Sukio, was too involved with her own concerns, so Mukitsu and his companion Kozo, supported a group of visiting samurai who had been sent to investigate the crimes.