1999年、新宿――。

人理を修復した藤丸立香たちカルデアの面々の前に新たなる特異点が現れた。
歴史の歪みを排除するため、
再びレイシフトした藤丸を待ち受けていたのは、
常夜の魔境と化した大都会だった。

完全犯罪計画が起動された世紀末の摩天楼を、
『新宿のアーチャー』と名乗る謎のサーヴァントとともに駆け抜ける！！

The year 1999, Shinjuku...

A new Singularity appeared before the protagonist and company at Chaldea, who thought they had restored humanity. To repair its distorted history, the protagonist Rayshifts once again, only to end up in a metropolis that has transformed into a territory of malice locked in a perpetual night.

Alongside a mysterious Servant calling himself the "Archer of Shinjuku," the protagonist battles through the skyscraper built at the end of the century, where a perfect crime has been conceived!