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Shirou Emiya finds himself an unwilling participant in a deadly competition where seven Mages summon heroic spirits as servants to duel each other to the death. They compete for the chance to make a wish from the Holy Grail, which has the power to grant any wish. Shirou is unskilled as a mage and knows nothing of the Holy Grail War, but he and his servant, Saber, enter into a temporary partnership with another Mage, Rin Tohsaka. However, problems arise between Shirou and Rin's servant, Archer, who seems to seriously despise him.