Explorer Bruce Wayne accidentally unleashes an ancient evil, and returns to Gotham after being away for two decades. There, Batman battles Lovecraftian supernatural forces and encounters allies and enemies such as Green Arrow, Ra's al Ghul, Mr. Freeze, Killer Croc, Two-Face and James Gordon.

Explorer Bruce Wayne accidentally unleashes an ancient evil, and returns to Gotham after being away for two decades. There, Batman battles Lovecraftian supernatural forces and encounters allies and enemies such as Green Arrow, Ra's al Ghul, Mr. Freeze, Killer Croc, Two-Face and James Gordon.