In the aftermath of the last battle, only four Servants remain.  Two of them inhabit Ryudou Shrine, making the next fight a dangerous one, as Shirou will have to face Assassin and Caster within their domain. Unfortunately, Shirou doesn't have time to strategize when one of his closest friends is taken there to be a sacrifice. Even with Saber and Rin by his side, Shirou, rushes into battle at a great disadvantage, while another Servant from Saber's past, emerges onto the scene...