Set during the Edo period, Zan follows the life a ronin, Mokunoshin Tsuzuki, and those around him. Mokunoshin Tsuzuki spends time in a village helping farmers there. To keep his sword skills sharp, he spars daily with a farmer's son Ichisuke. His sister Yu watches them. Meanwhile, the nation is about to undergo major unrest and potentially a civil war. A group of outlaw ronin led by Sezaemon Genda enters the village.
