The story starts from zero, a beginning…
The Holy Grail War -in this ultimate battle field, in order to obtain the power of the "Holy Grail" that makes one's any unattainable wish, seven "masters" summon "servants" and fight against each other until the last one survives….
After three inconclusive Holy Grail Wars, the fourth battle has finally started.
Hoping to win the battle, each master is heading to the new battlefield called "Fuyuki".
However, there is a man who is confused and struggling being unable to find a meaning of the war --his name is Kirei Kotomine.
He wonders why he is appointed to this task, but without any answer, he encounters his archrival -his name is Kiritsugu Emiya, a master who craves for the miracle Holy Grail most of all.
The untold truth of "the Fourth Holy Grail War" that had occurred 10 years before "Fate/stay night"--- the truth about the battle fought by Shiro's adopted father, Rin's father and young Kirei Kotomine is about to be revealed!