The “Why So Serious?” ComicCon event was designed to engage fans in non-traditional ways that brought the world of Gotham City off the film screen and into moviegoers’ lives. Using the largest Comic Book Convention to send fans off on an online/offline collaborative scavenger hunt not only brought the property to life, but also reflected the psychopathic madness of the film's iconic villain – the Joker. Players were engaged on their mobile phones, through their email, on the web, through physical objects, activities and puzzles in real world locations to build brand awareness and buzz for The Dark Knight.

10,000 defaced dollar bills were produced featuring a ‘tagged’ George Washington and the phrase “Why So Serious?” An interactive website, whysoserious.com, contained GPS coordinates, puzzles, a countdown and instructions from the Joker. At zero hour, a phone number was written in the sky and an interactive scavenger hunt was launched. Fans onsite and online worked together in innovative activities that included painting their faces, dialing phone numbers, looking for clues in architecture, stealing Gotham Girl cookies and more - all culminating in a documented kidnapping of one of their own. Was this all just an elaborate set-up by the Joker?