"Batman is a complex character, and Two-Face comes a little bit from the same world," Eckhart told the site. "But [at the same time], he's apart from it."
"I'm looking for the tension between the two, the similarities between the two," Eckhart added. "I want to find what's similar to Batman, and then find what's opposite to him."
In the DC Comics on which the film is based, Dent is the Gotham City district attorney who is permanently scarred when a criminal throws sulfuric acid in his face, resulting in a burn that leaves the entire left side of his body mutilated beyond repair. Unable to cope with his deformity, Dent's long-repressed anger surfaces, creating a split personality and a battle for his overall instincts. The Dark Knight opens in the summer of 2008.