Before the release of Batman Begins, screenwriter David S. Goyer writes a treatment for two sequels which introduce the Joker and Harvey Dent. Goyer, who wrote 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.

2006

 27/7 – The Australian press reports that Heath Ledger has been offered the role of The Joker in the as yet untitled sequel to Batman Begins, reportedly beating Robin Williams and Paul Bettany to the part.

31/7 – Warner Bros officially announces the beginning of production of The Dark Knight, sequel to Batman Begins.

Aug – Producer Charles Roven announces that principal photography of the film will begin in March 2007.   This date is eventually put back to April.

Oct – Location manager Robin Higgs visits Liverpool, Yorkshire, Glasgow, and parts of London, seeking suitable locations for shooting.

2007

 21/2 – Aaron Eckhart is signed to play the role of Harvey Dent (Two-Face ), the role previously played by Tommy Lee Jones in Batman Forever (1995)..

18/4 – Shooting of the film’s prologue takes place in Chicago until the 24^th April.

24/4 – Fire-fighters are called to a blaze at an empty post office building in Chicago being used as the Gotham National Bank for the film.  

29/5 – USA Today reports that Christopher Nolan plans to shoot sections of the film in the IMAX format.

 May - 42 Entertainment launches a viral marketing campaign centred around the film’s ‘Why So Serious’ tagline.

9/6–Sep – Shooting of the film takes place in Chicago.

Jul – 42 Entertainment launches WhySoSerious.com during Comic-Con International.

24/9 – Technician Conway Wickliffe is killed while planning a Batmobile stunt in a special effects facility near Chertsey, England.   Wickliffe was following the Batmobile on a racetrack when his car crashed into a tree.

Oct – The explosion of a rigged 200-foot fireball at the defunct Battersea Power Station for an opening sequence of the film sparks calls from local residents fearing a terrorist attack.

31/10 – The film’s website launches a scavenger hunt instructing visitors to unearth clues at locations in major cities throughout the US.

6/11 – Filming takes place in Hong Kong until 11^th November.

2008

 22/1 - Heath Ledger dies of an accidental overdose.

15/5 - Six Flags Great America and Six Flags Great Adventure theme parks open the $7.5 million Dark Knight roller coaster.

4/7 – The Toyota Formula One team race with a livery featuring the Batman insignia and ‘The Dark Knight’ at the 2008 British Grand Prix.

14/7 – The world premiere of The Dark Knight takes place at an IMAX theatre in New York City.   Composers James Newton Howard and Hans Zimmer play part of the film score live.

18/7 – The film goes on general release and sets a new midnight record with box office takings of $18.5 million - $1.6 million more than the previous record set by Star Wars Episode III: Revenge of the Sith in 2005.

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