The Dark Knight: Final Joker Scene

JOKER
You just couldn't let me go, could you? This is what happens when an unstoppable force meets an immovable object. You truly are incorruptible, aren't you, huh? You won't kill me out of some misplaced sense of self-righteousness, and I won't kill you because you're just too much fun. I think you and I are destined to do this forever.

BATMAN
You'll be in a padded cell forever.

JOKER
Maybe we can share one. You know they'll be doubling up at the rate the inhabitants of this city are losing their minds.

BATMAN
This city just showed you that it's full of people ready to believe in good.

JOKER
Until their spirit breaks completely. Until they get a good look at the real Harvey Dent, huh? And all the heroic things he's done. You didn't think I'd risk losing the battle for Gotham's soul in a fist-fight with you? No, you need an ace in the hole; mine's Harvey.

BATMAN
What did you do?

JOKER
I took Gotham's White Knight and brought him down to our level. It wasn't hard. See, madness, as you know, is like gravity: all it takes is a little push. (Laughter)