Hugh Jackman, Ryan Phillippe, Liev Schreiber, and Josh Lucas expressed interest in the role of District Attorney Harvey Dent.

As a joke, one bat suit was made with nipples. It was presented to Christian Bale as the real bat suit, but he knew instantly it was a joke, having seen a few design pictures during preproduction. He did pose for some publicity photos in the nipple suit.

This is the first Batman film to not have Batman in the title.

At the time when the Penguin was rumored to be in the movie, Bob Hoskins appeared as a fan favorite. He stated that he would have loved to portray the role and work with Christopher Nolan, calling him a fantastic director. Nolan then stated he had no intention of using the Penguin, calling him a too far-fetched character.

Robin Williams, Lachy Hulme, Paul Bettany, and Adrien Brody all expressed interest for the role of the Joker before Heath Ledger was cast.

When asked, Why Heath Ledger as the Joker? Christopher Nolan said, Because he’s fearless.

Dwight Yoakam turned down two roles in this movie. Originally he was offered the part of a cop; then he was offered to play a banker who had dealings with the Joker (Heath Ledger). Yoakam passed on both roles because he was working on a Buck Owens tribute album.

Turning down a salary estimated at between $1 million and $2 million an increase over the roughly $1 million she was believed to have earned for Batman Begins (2005) Katie Holmes chose not to reprise her role as Rachel Dawes. This was due to what was described as scheduling conflicts.

Jerry Robinson, who is credited as one of the original creators of the Joker, served as a consultant on the film.

Before Maggie Gyllenhaal replaced Katie Holmes in the role of Rachel Dawes, both Rachel McAdams and Emily Blunt were rumored for the part.

While filming on the streets of Chicago in April 2007, the filming was carried out under the fake movie title Rory’s First Kiss. Fliers regarding the filming carried this fake title, complete with a fake RFK logo for the movie and an address for the films production offices.

One of the extras military uniforms has the name Philo on it, after the films extras casting director, Joan Philo.

On Thanksgiving weekend, 2007, fake four page tabloid size Gotham Times newspapers were distributed at various public events. Headlined City at War Batman Saves Entire Family, every article teased events in the film, and everything in the handout was geared toward the film, including the weather (Gloomy and overcast) and advertisements for Gotham National Bank, the Gotham Girl Guides and recruitment for the Gotham Police Department.

The Jokers character is based on his first two appearances in the comic books, as well as his portrayal in the graphic novel The Killing Joke. To prepare for the role, Heath Ledger lived alone in a hotel room for a month researching the character and developing his performance, which he claims is based upon Sid Vicious and the character of Alex in A Clockwork Orange (1971). Ledger found the role extremely difficult, and suffered insomnia as a result.

Director Christopher Nolan and co-writers Jonathan Nolan and David S. Goyer decided not to explore the origins of the Joker in order to portray the character as absolute.

Christopher Nolan cites the film Heat (1995) as a major influence on this movie.

Off-duty Chicago Police Officers were requested to play Gotham Police officer extras.

Elaborate, interactive marketing campaigns were launched in the months leading up to the release of this film. One of which was an event at the 2007 San Diego Comic-con called Why So Serious, which involved fans following clues hidden around the city. The legions of Joker-painted fans ended up congregating in the street across from the convention center, where one of their numbers was welcomed into a black Escalade (with Gotham license plates) that had just pulled up. After a moment the fan started screaming and the SUV sped away. Later that day, a Gotham City newspaper was circulated reporting that a man believed to be the Joker was found beaten to death. Included were crime scene photos of the fan who had gotten into the Escalade, and a mention that he was found with a playing card in his hand, on which was scribbled See you in December.

Heath Ledgers sudden death on January 22, 2008 prompted immediate speculation as to the state of this film. Late the same day, Waner Bros. released a statement declaring that Ledger had completed all his scenes and post-production work, thus making the Joker the actors final completed appearance in a film.

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