Surrounded by a forest and a gated entrance, the Grace Field House is inhabited by orphans happily living together as one big family, looked after by their "Mama," Isabella. Although they are required to take tests daily, the children are free to spend their time as they see fit, usually playing outside, as long as they do not venture too far from the orphanage — a rule they are expected to follow no matter what. However, all good times must come to an end, as every few months, a child is adopted and sent to live with their new family... never to be heard from again.

However, the three oldest siblings have their suspicions about what is actually happening at the orphanage, and they are about to discover the cruel fate that awaits the children living at Grace Field, including the twisted nature of their beloved Mama.

Ganta Nakami is a high school student who suffers from insomnia. He meets Isaki Magari, a girl with the same condition. A relationship forms as they share a secret and catch up on their sleep in their school’s abandoned observatory.

魔术师们为追寻实现一切心愿的愿望机「圣杯」，而召唤英灵借以彼此竞争的争夺战──圣杯战争。于日本这片土地举行的第五次圣杯战争终结后数年，美国西部雪原市(史诺菲尔德)出现下一场斗争──那是充满虚伪的圣杯战争。
聚集于虚伪台座的魔术师与英灵们。即使深知这是场虚伪的圣杯战争──他们仍旧在此之上不断舞动。真伪即在遥远的彼岸。并非为了圣杯──也非为其他任何事物，而是为贯彻他们自身的信念。然而就在此刻，注满容器的究竟是虚伪或真实，还是说……
TYPE-MOON高人气视觉小说「Fate」，由成田良悟所描绘的新篇章！