If you look at the box office numbers, it's mathematically impossible that you haven't seen The Dark Knight. And if you really haven't somehow, honestly, what are you doing? Thus, I'm unapologetic about posting this spoiler from an interview with Aaron Eckhart:
CS/SHH!: Is Harvey Dent alive? Aaron Eckhart: No. He is dead as a door nail.
CS/SHH!: So he's not coming back?
Eckhart: He ain't coming back baby!
CS/SHH!: I was hoping he would.
Eckhart: No. I asked Chris [Nolan] that question and he goes, "You're dead" before I could even get the question out of my mouth. "Hey Chris, am I?" "You're dead!" Alright, cool.
CS/SHH!: That's not a problem in comic book movies. You could still come back.
Eckhart: I think in contract negotiations it's a problem.
CS/SHH!: So you were never signed on for another film?
Eckhart: No, I'm not coming back. I think unfortunately, Heath [Ledger] was supposed to go on and that didn't work out. I'm nobody. I'm a cog. I have no say over this sort of stuff.
Yessss. This is going to make my Harvey Dent rookie card worth so much more. And, yeah, Eckhart, I guess the whole Heath Ledger thing really didn't "work out," did it.