Ever since Heath Ledger's death last month, there has been much speculation in the entertainment press about how Warner Bros. might alter its marketing for The Dark Knight. Bat-fans will reportedly get their first hint of this new approach next month.

According to DarkHorizons.com, the next trailer for The Dark Knight is slated to debut with Warners' prehistoric epic 10,000 B.C., which opens March 7th.

The site adds that this new trailer, unlike the Joker-heavy first one, will feature more of Christian Bale and Aaron Eckhart as Bruce Wayne and Harvey Dent, respectively. It was previously reported that Warners had always intended on building the initial marketing phase for The Dark Knight around the Joker before switching the focus to Dent.
Dark Knight director Christopher Nolan has said that while the Joker is an important character in the film, the main story arc belongs to District Attorney Harvey Dent
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