Muichiro rescues Kotetsu before heading to rescue Haganezuka and Kanamori. Meanwhile, Tanjiro, Nezuko, and Genya are facing off against the demons who have split into four separate bodies.
Upon arriving to the village, Mitsuri rushes to Tecchin and finds that all of his guards have been defeated. Muichiro is being guided by Kanamori to the studio to receive his sword.
Muichiro is trapped in water by Gyokko's Blood Demon Art. Tanjiro and his comrades have successfully severed the necks of the four demons, but they realize that they cannot be defeated this way.
Tanjiro encounters Muichiro Tokito and Kotetsu arguing. Muichiro is demanding that a "certain key" which is used to operate a battle-type Doll, Yoriichi Type Zero, that mimics the movement of a certain real-life swordsman be handed to him.
Yoriichi Type Zero is destroyed at the end of Tanjiro's training, but a sword from over 300 years ago appears from inside. Haganezuka appears and takes the sword with him to perform a grueling whetting process.
An Upper Rank Demon has been defeated for the first time in a hundred years. Meanwhile, Tanjiro discovers that he has upset Haganezuka after chipping his sword and decides to talk to him in person.