The Dark Knight Development
Before the release of Batman Begins, screenwriter David S. Goyer wrote a treatment for two sequels which introduced the Joker and Harvey Dent. His original intent was for the Joker to scar Dent during the Joker's trial in the third film, turning Dent into Two-Face.
Goyer, who penned the first draft of the film, cited the DC Comics 13-issue comic book limited series Batman: The Long Halloween as the major influence on his storyline. While initially uncertain of whether or not he would return to direct the sequel, Nolan did want to reinterpret the Joker on screen.
On July 31, 2006, Warner Bros. officially announced initiation of production for the sequel to Batman Begins titled The Dark Knight; it is the first live-action Batman film without the word "Batman" in its title, which Bale noted as signaling that "this take on Batman of mine and Chris' is very different from any of the others."
After much research, Nolan's brother and co-writer, Jonathan, suggested the Joker's first two appearances, published in the first issue of Batman (1940), as the crucial influences. Jerry Robinson, one of the Joker's co-creators, was consulted on the character's portrayal.
Nolan decided to avoid divulging an in-depth origin story for the Joker, and instead portray his rise to power so as to not diminish the threat he poses, explaining to MTV News, "the Joker we meet in The Dark Knight is fully formed...To me, the Joker is an absolute. There are no shades of gray to him – maybe shades of purple. He's unbelievably dark. He bursts in just as he did in the comics."
Nolan reiterated to IGN, "We never wanted to do an origin story for the Joker in this film," because "the arc of the story is much more Harvey Dent's; the Joker is presented as an absolute. It's a very thrilling element in the film, and a very important element, but we wanted to deal with the rise of the Joker, not the origin of the Joker."
Nolan suggested Batman: The Killing Joke influenced a section of the Joker's dialogue in the film, in which he says that anyone can become like him given the right circumstances.
Nolan also cited Heat as "sort of an inspiration" for his aim "to tell a very large, city story or the story of a city": "If you want to take on Gotham, you want to give Gotham a kind of weight and breadth and depth in there. So you wind up dealing with the political figures, the media figures. That's part of the whole fabric of how a city is bound together."
According to Nolan, an important theme of the sequel is "escalation," extending the ending of Batman Begins, noting "things having to get worse before they get better."
While indicating The Dark Knight would continue the themes of Batman Begins, including justice vs. revenge and Bruce Wayne's issues with his father, Nolan emphasized the sequel would also portray Wayne more as a detective, an aspect of his character not fully developed in Batman Begins.
Nolan described the friendly rivalry between Bruce Wayne and Harvey Dent as the "backbone" of the film. He also chose to compress the overall storyline, allowing Dent to become Two-Face in The Dark Knight, thus giving the film an emotional arc the unsympathetic Joker could not offer. Nolan acknowledged the title was not only a reference to Batman, but also the fallen "white knight" Harvey Dent.
The Dark Knight Filming
While scouting for shooting locations in October 2006, location manager Robin Higgs visited Liverpool, concentrating mainly along the city's waterfront. Other candidates included Yorkshire, Glasgow, and parts of London.
In August 2006, one of the film's producers, Charles Roven, stated that its principal photography would begin in March 2007, but filming was pushed back to April.
For its release in IMAX theaters, Nolan shot four major sequences in that format, including the Joker's opening bank robbery and the car chase midway through the film, which marked the first time that a feature film had been even partially shot in the format. The cameras used for non-IMAX 35 mm scenes were Panavision's Panaflex Millennium XL and Platinum.
For fifteen years Nolan had wanted to shoot in the IMAX format, and he also used it for "quiet scenes which pictorially we thought would be interesting." The use of IMAX cameras provided many new challenges for the filmmakers: the cameras were much larger and heavier than standard cameras, and produced noise which made recording dialogue difficult.
In addition, the cameras had short film loads ranging from 30 seconds to two minutes and the cost of the film stock was much greater than standard 35mm film. Nevertheless, Nolan said that he wished that it were possible to shoot the entire film in IMAX: "if you could take an IMAX camera to Mount Everest or outer space, you could use it in a feature movie."
In addition, Nolan chose to edit some of the IMAX sequences using the original camera negative, which by eliminating generation loss, raised the film resolution of those sequences up to 18 thousand lines.
Warner Bros. chose to film in Chicago for 13 weeks, because Nolan had a "truly remarkable experience" filming part of Batman Begins there. Instead of using the Chicago Board of Trade Building as the location for the headquarters of Wayne Enterprises, as Batman Begins did, The Dark Knight shows Wayne Enterprises as being headquartered in the Richard J. Daley Center.
While filming in Chicago, the film was given the false title Rory's First Kiss to lower the visibility of production, but the local media eventually uncovered the ruse. Richard Roeper of the Chicago Sun-Times commented on the absurdity of the technique, "Is there a Bat-fan in the world that doesn't know Rory's First Kiss is actually The Dark Knight, which has been filming in Chicago for weeks?"
Production of The Dark Knight in Chicago generated $45 million in the city's economy and created thousands of jobs. For the film's prologue involving the Joker, the crew shot in Chicago from April 18, 2007 to April 24, 2007.
They returned to shoot from June 9, 2007 to early September. Noticeably, unlike Batman Begins, less CGI was used to disguise Chicago. Many recognizable locations were used in the film, like the Sears Tower, Navy Pier, 330 North Wabash, the James R. Thompson Center, Trump International Hotel and Tower, LaSalle Street, The Berghoff, Randolph Street Station, and Hotel 71.
An old Brach's factory was used as Gotham Hospital. The defunct Van Buren Street post office doubles as Gotham National Bank for the opening bank robbery. Several sequences, including one car chase, were shot on the lower level of Wacker Drive. The Marina City towers also appear in the background throughout the movie.
Pinewood Studios, near London, was the primary studio space used for the production. While planning a stunt with the Batmobile in a special effects facility near Chertsey, England in September 2007, technician Conway Wickliffe was killed when his car crashed.