In the city of Snowfield, a fresh Holy Grail War looms, setting magi against each other in fierce battles to claim the coveted title of Master by summoning heroic spirits known as Servants. The victor is promised a wish fulfillment, but this iteration of the conflict turns out to be a flawed replica of the Third Holy Grail War. As the Mage's Association in London takes notice, Flatt Escardos, mentored by the experienced Lord El-Melloi II from a previous Holy Grail War, defies expectations and enters the fray as a Master. Amidst this distorted contest blurring the lines between Master and Servant, the factions struggle to avert Snowfield's descent into utter turmoil.