Yagyu Jubei, the oldest son of the Shogunate Superintendent Officer Tajima-no-kami Yagyu Munenori, the best swordsman on earth!
The time is the 11th year of Kanei (1634) when the third Shogun Iemitsu Tokugawa ruled Japan. Jubei's father Munenori suddenly asks him to come home while Jubei is on a samurai training journey. After not seeing his son for ten years, Munenori tells Jubei about the conspiracy of overturning the present Shogunate plotted by the warriors of Suruga Dainagon Tadanaga, who competed with Iemitsu for the Shogun position and was forced to commit seppuku. The ringleader of the conspiracy is a fearful swordsman and the ex-advisor of Tadanaga, Kageyu Toda. Jubei's secret trip has begun in order to erase the root of all possible conspiracies plotted all over the country...
