A decapitation at the hands of the shogun's monstrous misbegotten son kicks off the action and draws nomadic Nemuri Kyoshiro (Raizô Ichikawa) into more sword-fighting adventures when he's blamed for the beheading. Meanwhile, the head-chopper's mother is busy knocking off the shogun's lawful heirs to secure the shogunate for her son.
Nemuri Kyoshiro, a youthful and cynical ronin with unparalleled skill, is approached by both sides in a game of corruption, ambition, and double crosses. The leader of the Kaga clan, who thinks he has killed his smuggling partner, fears that the shogunate will discover his illegal activities. He learns of evidence that will prove his guilt. Meanwhile, his partner is not dead, and, assisted by a master of Shorenji boxing, is looking for revenge and for his loot. The Kaga leader sends the beautiful Chisa to enlist Nemuri's aid. The unexpected happens: the hard-bitten Nemuri falls in love. Can he protect her, topple the criminals, and avoid the boxer's deadly skill?