Fate/stay night - 2x12 - The Final Decision- Followmy.tv

While returning home from a trip in the next town, Shirō, Rin, and Saber find themselves inside a magical barrier, and they are ambushed by Caster and several water Golems. Caster reveals she has taken Taiga hostage and threatens to kill her unless Shirō hands over his magical circuits to her. When Shirō refuses, Caster tells him that she knows about the fire that he survived ten years ago, then claims her knowledge of a method to summon the Holy Grail without any further fighting, which can only be accomplished by Saber's mana.