Producer David Goyer said Batman Begins writer/director Christopher Nolan wasn't willing to jump into a second Batman movie without first being convinced there was a compelling reason to a sequel. After tossing around ideas as to where the story would go, Goyer, Christopher Nolan and his screenwriting partner/brother Jonathan came up with the basic ideas of ground to cover in The Dark Knight. The second film introduces politician Harvey Dent (Aaron Eckhart) and one of the most recognizable villains in films and comics, The Joker (Heath Ledger), and takes the franchise down an even darker path than the one tread in Batman Begins.
"I think the big challenge really in doing a sequel is to build on what you've done in the first film, but not abandon the characters, the logic, the tone of the world that you created for the first film," explained Nolan. "So there are elements the audience will expect you to bring back that you need to bring back. You also have to balance that with the need to see something new and to see something different, and that's been the challenge through the whole of making the film."
Tim Burton's Batman Returns was typical of Burton's quirky, dark style of filmmaking but with The Dark Knight Nolan outdoes Burton, taking the Batman franchise into even more disturbing territory. "You certainly can push it too far, but interestingly there are different ways to be disturbing," offered Nolan. " I mean, I don't talk a lot about the previous films because I didn’t make them and they're not mine to talk about, but certainly if you look at Batman Returns with Danny DeVito as The Penguin, eating the fish and everything, there are some extraordinarily disturbing images in that movie. But they're coming at it from a surreal point of view."
"I think the ways in which this film is disturbing are different. We try to ground it a little more in reality and so I suppose there's a sense there that might get under your skin a little more, if it relates to the world that we live in. As I say though, there are different tones that can be taken with adapting this character to the movies. Indeed, in the comics, one of the things that Paul Levitz at DC Comics first talked about when I first came onboard for Batman Begins is that Batman is a character who traditionally is interpreted in very different ways by the different artists and writers who've worked on it over the years. So there's a freedom, and an expectation even, that you will actually put something new into it, that it'll be interpreted in some different way. I think of any of the superheroes Batman is the darkest. There is an expectation that you're going to be dealing with more disturbing elements of the psyche. That's the place that he comes from as a character, so it feels appropriate to this character."
The Dark Knight pushes the PG-13 limit (it earned its rating for intense sequences of violence and some menace). Nolan knew that was the rating the studio was targeting throughout production and kept that in mind when crafting the film. "…Part of my creative process is knowing the tone of the film that I'm going to wind up with. So always knowing that this was going to be a PG-13 movie and that we want kids and families to go see this, you think along those lines and you don't really tend to come up with stuff that's completely beyond the pale."
Nolan believes that although it does push the PG-13 boundary, The Dark Knight never really crosses the line into 'R' territory. "If you assess the film carefully and analyze it with other films, it's not a particularly violent film actually. There is no blood. Very few people get shot and killed, compared with other action films," said Nolan. "There's plenty violence in the film, believe me. We tried to shoot it and dress it in a very responsible way so that the intensity of the film comes more from the performances and the idea of what's happening and what might happen. A lot of the intensity comes from the threat of those things that may happen that then don't. There's definitely an intensity to that."
"I think the MPAA were very responsible in their assessment of the movie. I made it very clear to them that I'd gone into this knowing that it had to be a PG-13 and every day on set when we were dealing with violent issues I would be careful to tone things down and say, 'Okay, we're not going to use any blood squibs. We're not going to shoot things that can't possibly be in the film.' So it's a very bloodless film. We're dealing with a hero who won't carry a gun and who won't kill people, which is almost unique in terms of an action film. It's a conversation that I've had with the studio, with the MPAA and everyone else at different stages to say that it's very hard actually making one of these huge-scaled films with a heroic figure who's not prepared to kill people. But I think it's an interesting challenge and I think that it takes the story more interesting places."
Warner Bros Pictures never attempted to intercede in the filmmaking process and never tried to get Nolan to lighten the tone or change the direction of The Dark Knight story. "I don't really fight with the studio. I never have because I think you lose. It's quite a powerful organization that's paying for the whole film. My experience and my way of working with them has been a very positive collaboration, really. I think the thing that I try to do as a filmmaker is try to be very communicative to the studio and to everyone else. I try to really explain to them what it is that I am doing so that any big disagreements about the nature of what the thing should be are had right on Day One of putting the script together, rather than when you're actually shooting the film or editing the film," said Nolan.