The Dark Knight is a 2008 superhero film directed, produced and co-written by Christopher Nolan. Based on the DC Comics character Batman, the film is part of Nolan's Batman film series and a sequel to 2005's Batman Begins. Christian Bale reprises the lead role of Bruce Wayne/Batman, with Michael Caine, Gary Oldman and Morgan Freeman returning as Alfred Pennyworth, James Gordon and Lucius Fox, respectively. The film introduces the character of Harvey Dent (Aaron Eckhart), Gotham's newly elected District Attorney and the cohort of Bruce Wayne's childhood friend Rachel Dawes (Maggie Gyllenhaal), who joins Batman and the police in combating the new rising threat of a criminal calling himself the "Joker" (Heath Ledger).
Nolan's inspiration for the film was the Joker's comic book debut in 1940, and the 1996 series The Long Halloween, which retold Two-Face's origin. The Dark Knight was filmed primarily in Chicago, as well as in several other locations in the United States, the United Kingdom, and Hong Kong. Nolan used an IMAX camera to film some sequences, including the Joker's first appearance in the film.
In Gotham City, the Joker and his accomplices rob a bank used by the local mob as a front for money laundering. Batman and Lieutenant James Gordon decide to include new district attorney Harvey Dent, who is dating Bruce Wayne's childhood sweetheart Rachel Dawes, in their plan to eradicate the mob. Bruce later meets Dent and offers him a fundraiser after realizing his sincerity. Mob bosses Sal Maroni, Gambol, and the Chechen meet to discuss the new pressure on their crime operations. Lau, a Chinese mafia accountant, informs them that he has hidden their money and fled to Hong Kong in an attempt to preempt Gordon's plan to seize their funds and hide from Dent's jurisdiction. The Joker barges into the meeting, warning that Batman will come after Lau, and instead offers to kill Batman for half of the funds. They flatly refuse, and Gambol places a bounty on the Joker's head. Not long after, the Joker kills Gambol and takes control of his gang.
