Joker (Nolanverse)

"You wanna know how I got these scars? My father was... a drinker... and a fiend. And one night, he goes off crazier than usual. Mommy gets the kitchen knife to defend herself. He doesn't like that. Not. One. Bit. So, me watching, he takes the knife to her, laughing while he does it. He turns to me and says, "Why so serious?" He comes at me with the knife. "WHY SO SERIOUS?" He sticks the blade in my mouth... "Let's put a smile on that face!" And... why so serious?"

- Joker saying out his fake backstory about his father

The Joker depicted in The Dark Knight is often considered the darkest version of the Clown Prince of Crime since his early beginnings in DC comics (prior to a softening of character) perhaps somewhat due to the popularity of Dark Knight some of this Joker's extreme sociopathy has began to sink into the mainstream Joker but in general they are still considered very different criminals in the way they act and think.

The Dark Knight
The Joker, played by the late Heath Ledger, is the main antagonist in the movie The Dark Knight. The Joker is a psychotic villain who claims to be an "agent of chaos," seemingly doing it for the sake of destroying the plans of others and causing maximum psychological and physical damage. In the film, the Joker rescinds his comic weapons in favor of explosives, knives and firearms. He is responsible for the death of Rachael Dawes and for the wounding and psychological manipulation of District Attorney Harvey Dent into Two-Face among others.



The Joker states that he won't kill Batman because he is simply too much “fun” and Batman won't kill him because of his “moral obligation.” In the movie, instead of trying to kill Batman, the Joker attempts to show Gotham and subsequently Batman that anyone can be as bad as the Joker under the right circumstances.

Fate
Heath Ledger died under mysterious circumstances of a drug overdose before the movie was released. Out of respect for him, the filmmakers did not even mention the Joker whatsoever in the following film, The Dark Knight Rises. Thus, it is unknown what happened to the Joker after he was arrested. But according to the original script of the third movie, it is likely stated that he was imprisoned far away from Gotham City, never to be heard from again. Another likely scenario is that he died by the time of Bane's revolution.

The novelization of 'Rises' places him as possibly the one and only prisoner of Arkham, (the way Rudolf Hess was in Spandau Prison) or perhaps he escaped. Nobody was really sure.

Trivia

 * Mark Hamill, no stranger to Joker, has called Ledger's performance absolutely terrifying and creepy.