Batman, along with many of his allies and adversaries, finds himself transported to feudal Japan by Gorilla Grodd's time displacement machine.

The Batman family has returned to the present to discover that Japan has disappeared, and a giant island - Hinomoto - is now in the sky over Gotham City. At the top sit the Yakuza, a group of superpowered individuals who reign without honor or humanity and look suspiciously like the Justice League. Now, it’s up to Batman and his allies to save Gotham!