In an interview with MTV’s Splash Page, Caine relates a conversation with a Warner Bros. executive in which Johnny Depp and Philip Seymour Hoffman were named in the parts of The Riddler and The Penguin:
“I was with [a Warner Bros.] executive and I said, ‘Are we going to make another one?’ They said yeah. I said, ‘How the hell are we going to top Heath? And he says ‘I’ll tell you how you top Heath — Johnny Depp as The Riddler and Philip Seymour Hoffman as The Penguin.’ I said, ‘S–t, they’ve done it again!’” [Laughs]
Caine’s unnamed studio source may have the inside track, or he simply may have been answering the question with a “dream cast.” Heck, there aren’t even any indications a script has been written for the third film.
Although there have been many rumors about who the villains will be in the sequel to The Dark Knight and which actors might play them, Depp and Hoffman as The Riddler and The Penguin is the one with the most traction.
However, earlier this month, Depp said he hadn’t been cast in the movie. Still, he said, “It seems like it’d be a fun gig for a while, yeah.”