Oyuki, the daughter of a master swordsman in the Yaegaki-style, is a skilled practitioner of the secret technique "flying sword". She embarks on a journey alongside the naive samurai Isawa no Fujiyoshi, hailing from a peasant background, and Choshi no Yosaburo, an aspiring chivalrous rogue from a fishing village. Together, they travel and seek to punish the wicked.