In a Holy Grail War, Mages (Masters) and their Heroic Spirits (Servants) fight for the control of the Holy Grail—an omnipotent wish-granting device said to fulfill any desire. Years have passed since the end of the Fifth Holy Grail War in Japan. Now, signs portend the emergence of a new Holy Grail in the western American city of Snowfield. Sure enough, Masters and Servants begin to gather... A missing Servant class... Impossible Servant summonings... A nation shrouded in secrecy... And a city created as a battleground. In the face of such irregularities, the Holy Grail War is twisted and driven into the depth of madness. Let the curtain rise on a masquerade of humans and heroes, made to dance upon the stage of a false Holy Grail.

Lucifer and company face new challenges, form new alliances and...now there's a baby! Your favorite otherwordly crew returns in this continuation.

A world where it has been established that people routinely swing between slightly different parallel worlds... Koyomi Takasaki, who lives with his mother following his parents' divorce, enrolls in a local university prep school. Due to the atmosphere concentrated on studies and his social awkwardness, Koyomi is unable to make friends. One day, he is suddenly approached by his classmate Kazune Takigawa, who tells him that she has travelled from the 85th world where she and Koyomi are lovers.

As a child, Uta—the Red Hair Pirates' ex-musician and Monkey D. Luffy's childhood friend—promised that she would build a new era of freedom by performing joyful music for the world. Luffy and the Straw Hat Crew arrive at Uta's first ever live concert, where many fans have gathered to enjoy the diva's otherworldly singing. Due to a childhood trauma, Uta bears a deep-seated hatred for pirates; her happy reunion with Luffy is cut short when she learns that he has since become one. Luffy's refusal to change his ways results in Uta unleashing her powers on the Straw Hats. The crew soon learns that their minds have already been trapped in Uta's dream world since the beginning of the concert, while their unconscious bodies remain asleep in the real world. With time quickly running out, the Straw Hats must find a way to escape the nightmare or be trapped in Uta's dream forever.