The second opus in the Batman Begins series was not only one of the biggest box office hits ever. Like every Hollywood mega-production, it benefited from a marketing plan that far surpasses the budgets of even the biggest French pictures. It was also developed as a transmedia concept, and a fairly considerable portion of the budget was allocated to developing transmedia elements designed not only for publicity purposes, but also as elements of a marketing strategy that would be incorporated into the story.
Among other things, an alternate reality game was created with a clue to start with: some playing cards left by the Joker (in various comic book stores on the West Coast) with the enigmatic inscription “I believe in Harvey Dent too”. This slogan later turned out to be the address of the first website dedicated to this gigantic scavenger hunt, which has been continually enriched by new events ever since. No fewer than 40 websites were subsequently created, along with a dedicated Wiki and some fan sites.
During the run-up to the theatrical release, the sharpest fans managed to get their hands on the last pre-release trailers by going to certain specific spots in a few big cities in the US after deciphering the riddles left by the Joker on various web sites. Not to mention the phoney election campaigns for Harvey Dent, another character in the movie. Or the press kits sent to certain journalists by the Joker himself in the form of a cake containing a real cell phone with a number to call for an exclusive scoop on other information.
All these elements made Dark Knight the must-see picture of the summer of 2008 and catapulted it to fourth place in all-time box office receipts.
This is an instance of transmedia marketing, but well-done marketing based on complementary contents of the film. A great many trailers and websites about Gotham City and Harvey Dent’s candidacy for district attorney succeeded in convincing not only hardcore fans, but also plenty of others, of the quality of the film itself.