The story follows the vigilante Batman, who is called upon to quell a maddening riot taking place in the infamous Arkham Asylum, a psychiatric hospital housing the most dangerous supervillains in Gotham City. Inside, Batman confronts many of his enduring rogues gallery, such as the Joker, Two-Face, and Killer Croc. As Batman ventures deeper, he discovers the origin of how the asylum was established, the history of its founder Amadeus Arkham, and the supernatural and psychological mystery that has been haunting the mansion.