The Holy Grail War is a battle between seven magicians who each summon a mythical hero to fight for their cause. Shirou, a twice orphaned high school boy, had so little magical talent that his foster father did not bother teaching him about the war and its meaning. Thanks to that lack of foresight, Shirou finds himself in a bit of a pinch when he accidentally summons a hero of the strongest class, and is sucked into the fray. The Grail grants the winner any wish they have. But driven by an unyielding sense of justice and self-sacrifice, for what will Shirou fight?