The 4th year of the Keian Era, Edo Period.
It has been several decades since the end of a turbulent, blood-soaked era.
People were enjoying peace and tranquility.
But, a battle between seven pairs of Masters and Servants is about to begin,
as the "Waxing Moon Ritual" unfolds in the shadows.
Miyamoto Iori, a young man in Asakusa, finds himself caught in the violence of a Holy Grail War.