Demon Slayer - Season 4

The Hashira, Sanemi and Iguro, along with their comrades head to an abandoned castle on top of a mountain for a mission, while Tanjiro is being treated at the Butterfly Mansion for the wounds he suffered at the Swordsmith Village. Later on, the Hashira gather at the Ubuyashiki Mansion to hold a Hashira meeting, where Muichiro reveals how the marks manifested. In an effort to strengthen the entire Demon Slayer Corps from the bottom up, the Hashira Training begins...

Kagaya's Kasugai Crow suddenly appears in front of Tamayo and invites her to the Demon Slayer headquarters — even though she is a demon. Meanwhile, after receiving a letter from Kagaya at the Butterfly Mansion, Tanjiro pays a visit to Giyu, who is not participating in the Hashira Training. At first, Tanjiro is rejected by Giyu but patiently continues to try to talk to him. Giyu, who gives in to Tanjiro's persistence, begins to share the reason why he won't participate in the training.

Tanjiro's wounds have healed, so he first visits the former Hashira, Uzui, to join the Hashira Training. Tanjiro's joy for the reunion with Uzui is short-lived, however, as he will now undergo basic training to boost his physical stamina.

After completing training with Uzui, Tanjiro visits the Tokito residence next. The Demon Slayer swordsmen who have already started the training are dispirited by Muichiro's intense training and harsh words. Tanjiro hears the swordsmen discussing if there's anything they can do about it...

After completing Mitsuri's training, Tanjiro heads to train with Iguro. When he arrives at the training site, Iguro is waiting for him, visibly angry. Will he be able to complete this horrifying training where he'll have to fix his sword skills?

Tanjiro and Zenitsu head to Himejima's training site deep in the mountains and reunite with Inosuke and Murata. Tanjiro first starts the training by being hit by a waterfall but struggles with the coldness and weight of the water.

During the boulder training, Tanjiro is able to move the boulder thanks to Genya's training advice. However, Tanjiro has used all of his power to do so and he is saved by Himejima after he collapses. Himejima, moved by Tanjiro's genuineness, begins to talk to him about his past...

During a silent night when the moon shines, Kagaya finally meets Muzan Kibutsuji, who appears at the Ubuyashiki Mansion. Kagaya is staying alive day-by-day through his steadfast desire to defeat Muzan, while Muzan dreams of eternity. What will these two, bound by a continuous thousand-year fate, talk about?