The Joker, Batman's archenemy, plots to gain control of Arkham Asylum, confine Batman inside with many of his incarcerated foes, and endanger Gotham City with hidden bombs in the main plotline of the game.
Most of the game's major characters are voiced by performers who have previously starred in DC Animated Universe-related media; Kevin Conroy, Mark Hamill, and Arleen Sorkin reprise their roles as Batman, the Joker, and Harley Quinn, respectively.