In the American city of Snowfield, a new Holy Grail War is about to erupt. Such ruthless confrontations pit against each other magic experts known as magi, who ascend to the status of Master by summoning Servants—heroic spirits of the past. The winner is thought to have any one of their wishes granted. However, it appears that the organization behind the present situation has merely managed to create an imperfect copy of the Third Holy Grail War. As the unusual ritual catches the attention of the Mage's Association in London, Flatt Escardos, the young apprentice of Lord El-Melloi II—a former participant of the Fourth Holy Grail War—travels to Snowfield and, to the great dismay of his teacher, joins the ranks of the Masters. In this fake conflict where the line between Masters and Servants is blurred, the different factions will have a hard time preventing the city of Snowfield from plunging into total chaos.

It is rumored in the martial world that a mystery white-haired girl suddenly appeared around the thief Feng Ling Er. She is so powerful that many martial arts masters can't defeat her. The girl's identity, the source of her power and her influence to the world all caused discussion among the public. But Feng Ling Er and the white-haired girl named Bai Yu Xiu never care about it. They travel the world with pleasure, unaware of a great conspiracy coming towards them.

With the promise of granting any wish, the omnipotent Holy Grail triggered three wars in the past, each too cruel and fierce to leave a victor. In spite of that, the wealthy Einzbern family is confident that the Fourth Holy Grail War will be different; namely, with a vessel of the Holy Grail now in their grasp. Solely for this reason, the much hated Magus Killer Kiritsugu Emiya is hired by the Einzberns, with marriage to their only daughter Irisviel as binding contract. Kiritsugu now stands at the center of a cutthroat game of survival, facing off against six other participants, each armed with an ancient familiar, and fueled by unique desires and ideals. Accompanied by his own familiar, Saber, the notorious mercenary soon finds his greatest opponent in Kirei Kotomine, a priest who seeks salvation from the emptiness within himself in pursuit of Kiritsugu. Based on the light novel written by Gen Urobuchi, Fate/Zero depicts the events of the Fourth Holy Grail War—10 years prior to Fate/stay night. Witness a battle royale in which no one is guaranteed to survive.