Before and after the Comic-Con International screening of "Batman: The Killing Joke," the film's cast and crew talked about the process of adapting Alan Moore and Brian Bolland's seminal DC Comics tale from page to screen. In particular, screenwriter Brian Azzarello and director Sam Liu spoke about the decision to introduce sex to the relationship between Batman and Batgirl.

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"The thing about this is that it's controversial, so we added more controversy," explained Azzarello. "I think she is stronger than the men in her life in this story. She controls the men in her life in this story."

"They both make mistakes, but she's the one who decides, 'I have to stop. There's a problem here, and I need to step away from this,'" Liu explained. "I think that comes from an emotional strength. I think she makes the decisions that strong people make."

"She comes off as a stronger character at the end of that arc," Azzarello agreed.

idk how to feel about this pic.twitter.com/gsBGHsYet5- ☕ (@AcroNite7) July 22, 2016

Warner Bros. Animation's "Batman: The Killing Joke" stars Kevin Conroy as Batman, Mark Hamill as the Joker, Tara Strong as Barbara Gordon and Ray Wise as Commissioner Gordon. Directed by Sam Liu ("Justice League vs. Teen Titans"), the film comes from a script by Eisner Award-winning writer Brian Azzarello. Bruce Timm and Sam Register are executive producers, and Alan Burnett is co-producer.

"Batman: The Killing Joke" will be available for Digital HD download on July 26, and arrives on Blu-ray/DVD on August 2.