Original title (JP): 劇場版「鬼滅の刃」無限城編 (Gekijō-ban `oni metsu no ha’ mugen-jō-hen, Demon Slayer: Kimetsu no Yaiba the Movie: Mugen Castle)

The Demon Slayer Corps plunge into Infinity Castle to defeat Muzan. However, the remaining Hashiras and the Demon Slayers who survived Tanjiro’s Final Selection are pitted against the remaining members of the Twelve Kizuki first.

https://www.themoviedb.org/movie/1311031