Heath Ledger may still be in the new Batman sequel?
Well, I know it sounds ridiculous at first, but hear me …. Nolan is very possible can put Ledger in the next Batman movie after it has been either removed, cut, or simply not used in The Dark Knight, and try to make the plot of the sequel in a way. Would be logistically very difficult to do, of course, but keep in mind, Nolan has chosen to keep the Joker in the movie and the death of Heath Ledger has been months before the release of TDK, so it could easily have cut certain sequences of the film and 2.5 hours to pull this off. What do you think? Not many images is necessary to obtain a significant impact on the film, have a better idea, imagine the size of a surprise, was the first time viewers of the movie "Seven" when they discovered who played the murderer. 
A similar effect can be used here.
First … The Dark Knight was the sequel to "Batman Begins" so that the third film is actually the third episode of the series .. But … is very possible … For Of course, it would be a major … but a scene of him behind bars, saying something dramatic ("rah rah rah rah rah rah … … … chaos reign) might have a strong impact … Then there is the idea of Harley … As you know the fans of Batman, Harley Quinn is a good companion to wildcards. She met The Joker as his psychiatrist, while incarcerated in Arcam madhouse. So …….. maybe a little scene of him talking to a woman who begins to terrorize Gotham in his name? Depending where the director is chosen to maximize their equipment for the plot, could be even some ideas of "Batman Beyond" series in which there is a body of troops Joker perhaps led by some crazy psychiatrist. is impossible to say for sure … rumors of a third movie has not yet been fully confirmed (plus some comments he escaped helped spread what is still the rumor). We'll see over time if …
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