Demons killed Tanjiro Kamado’s entire family and turned his younger sister Nezuko into a demon. The young man joined the Demon Slayer Corps. While the slayers train and prepare for the coming clash with the demons, Muzan Kibutsuji — the progenitor of all demons and the killer of Tanjiro’s family — appears at the estate of the Corps’ leader. The slayers rush to their leader’s aid, but Muzan Kibutsuji transports them to the Infinity Castle, the demons’ fortress.