The first installment in the series of fantasy swordplay action movies starring Riki Takeuchi. Muramasa, a mystical blade imbued with the grudges of those persecuted by the Tokugawa Shogunate, reawakens in the modern era. Yagyu Kengo, descendant of the Yagyu Clan and "sealmaster," faces off against the Shimazu Clan, who seek to exploit Muramasa's power for their own gain.