The Dark Knight is set in a fictional city.
Gotham City ( [ ˈɡɒθəm ] ) , or simply Gotham , is a fictional city appearing in American comic books published by DC Comics , best known as the home of Batman . The Dark Knight is a 2008 superhero film directed , co-produced , and co-written by Christopher Nolan . In the film , Bruce Wayne/Batman ( Bale ) , James Gordon ( Oldman ) and Harvey Dent ( Eckhart ) form an alliance to dismantle organized crime in Gotham City , but are menaced by a criminal mastermind known as the Joker ( Ledger ) who seeks to undermine Batman 's influence and create chaos .