A year has passed since his victory at the Sanctuary, and things finally seem to be turning around for Subaru. Emilia's group is more united than ever ahead of the royal selection, but the peace is short-lived. A letter from Anastasia, another candidate for the throne, invites Emilia to the aquatic city of Priestella, drawing everyone into a new journey. Unfortunately for them, a massive disaster is already unfolding beneath the surface of the city. The trap is sprung in an instant, and Subaru finds himself once again at the center of a merciless nightmare, where death once again knocks on his door with no escape. If you loved the first seasons, get ready: this new installment ramps up the action, desperation, and constant twists.