That's the word from Kevin Conroy, who plays the superhero in both Arkham Asylum games, who told attendees of the Chicago Comics & Entertainment Expo that the sequel will be "really, really dark", reports Comic Book Resources.
The veteran voice actor, who also played the hero in Batman: The Animated Series, also promised a "complicated" cast in the new game, revealing that a "lot of villains" would be featured.
Conroy was also said to have accidentally let slip that one of those villains may be the split-personality afflicted Two-Face, but refused to divulge further details.
The original Batman: Arkham Asylum was released late last year and featured some of Batman's most famous foes, including Poison Ivy, Scarecrow, Killer Croc and the Joker, who was voiced by Star Wars actor Mark Hamill.
It made a comeback last month with the launch of Batman: Arkham Asylum - Game of the Year Edition, which introduces an all-new 3D viewing mode.