Tsukitaro, a young man who comes to Edo, meets a blind girl named Ochiyo. Ochiyo’s father, the grinder Yasujiro, was asked to sharpen a sword called Kongomaru, which was planned to be presented to the shogun Iemitsu, but he died due to a yakuza attack. In addition, the sword was stolen, and Ochiyo’s sister was also kidnapped.