The Realm of Midgard. A Singularity in Time trapped in the time and rule of the Norse Gods. It encompasses an alternate version of Britain, Scandinavia Ireland, basically most of Europe, and is ruled by Odin, Thor, Baldr, Loki and the like.. But this isn't a Lost Belt from Fate Grand Order.. no.. the gods here be sinister.. terrible.. powerful.. and Rider, Saber and Mikoto are about to be thrown into the middle of it..

Mikoto, Arturia, and Okita are going to New York.. why? After the death of Mikoto's parents, she inherited an incredible sum of money, however, thanks to legal troubles and the cunning sly efforts of Mikoto's half American cousin Stacy Green, Mikoto is instead broke.. while her cousin gets all the money.. and without anything to continue paying for her school, Mikoto is risking losing what little future she has left... and amid this crisis, Okita Souji finds herself more and more fearful for Mikoto's wellbeing.. However.. this is the least of their worries... For the New York Faction of the Grail Wars.. are about to make their move..

In a desolate future.. 3000 years from our present.. a man named Sieg summons A Saber Class Servant . His intent.. to travel to the past.. to Camelot, to obtain the Holy Grail before it became corrupt so that he may obtain a precious wish for himself. But why? Meanwhile, in the Present day.. Chaldea, an angency that protects the Future of humanity faces a large problem. By next month, Humanity is destined to disappear from existence! Can Mikoto, Saber, and their friends find the cause in Camelot? Or is humanity doomed to expire by next month?

A month after the end of the Experiment 23 incident, Mikoto is busy trying to rebuild her life after the death of her parents with the help of her Servant and guardian Saber. However, as this happens, the Grail Wars begin to come into full swing, with Kakine and Berserker beginning to make their moves, as well as Aleister Crowley himself. Unfortunately, Mikoto is unable to focus much on her life or the Grail Wars due to the romantic advances of Touma Kamijou's servant Saber of Red, and the emergence of some old allies of Touma's magic dealings in Academy City. Can Mikoto convince Mordred that it's unrequited love.. or will she actually start falling for the weird aggressive gender-confused knight? (much to her immense chagrin).

Academy City. An independently governed City 30 years ahead of the future in science and technology, land locked in Japan, made up mainly of high schools, colleges, labs, and possessing a population mainly comprising of students and teachers. 60 percent of these students possess psychic powers and live as espers.. and one of the 7 most powerful of these espers, The Railgun, Mikoto Misaka, lives in this city. Mikoto has been orphaned for about 1 month now. Following the death of her family by unknown causes, she has been debating leaving Academy City to study in America. However, things change when she finds herself baring witness to two strange warriors called Archer and Assassin battling it out. And to make matters stranger, she is saved by a mysterious knight calling herself Saber. The Grail Wars of Academy City are about to begin.