The wandering swordsman, Ino Heihachiro, defeats Ichima, the youngest of the famed swordsmanship trio, the Nikis, but sustains an injury. In the mountains of Tohoku, he is aided by a young boy named Shosuke. Heihachiro finds refuge in the home of the boy's parents, Magoichi and Shino, only to discover that Magoichi was a skilled ninja from Koga. The peaceful days with the family are short-lived as Ichima, bent on revenge, along with his brothers Kurodo and Ryuma, pursue Heihachiro. Heihachiro and Magoichi head towards the duel's location, but the village headman, Seibei, blinded by the allure of gold dust in the mountains, abducts Shino...