Set at the end of the Edo period. With the approaching threat of foreigners, the Annaka lord's Katsuaki Itakura decided to train samurais by holding an excursion running through ten Gosato (about 58 km) along the mountain road. However, this movement is mistaken for treason by the shogunate, who decide to assassinate Katsuaki staying in the castle during the absence of samurais. Only one person, a man who knew that a crisis is approaching, in order to stop the plan, begins to run. ~~ Adapted from the novel "Edo marathon Samurai" by Dobashi Akihiro.