Trivia
* 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.
* The Dark Knight 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. Christopher 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. Sean Penn was the original choice.
* When asked, "Why Heath Ledger as the Joker?" Christopher Nolan said, "Because he's fearless."
* 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 will be serving as a consultant on the project.
* 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 film's production offices.
* One of the extra's military uniforms has the name "Philo" on it named after Joan Philo, the extra's casting director for the film.