It's official! Batman: The Killing Joke has been Rated R by the MPAA. But this isn't a marketing gimmick brought on by the success of the R-Rated superhero blockbuster Deadpool. The DC animated movie was announced before anyone knew Deadpool would prove to be such a box office monster. And many suspected that it would push the edges of PG-13 based on its DC Comics source material.

Batman: The Killing Joke is a direct-to-video feature-length animated movie based on the notoriously violent Alan Moore classic of the same name. This will mark the first ever DC Universe Original Movie to receive the R rating. And it's the second Batman movie to score such a rating, with an R-Rated Ultimate Edition of Batman v Superman: Dawn of Justice coming to Blu-ray, DVD and VOD sometime this summer. There is even a rumor that the Batman v Superman R-rated cut might land in theaters, but that hasn't been confirmed by Warner Bros.

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Mark Hamill is set to reprise his voice role as The Joker in The Killing Joke. Kevin Conroy is also returning to voice Batman alongside the vigilante's billionaire alter ego Bruce Wayne. Batgirl, aka Barbara Gordon, will be played by Tara Strong. The movie will serve as an origin story for The Joker. The iconic DC villain will also be seen in live-action this August in Suicide Squad, with Jared Leto taking on the character.

In Batman: The Killing Joke, The Joker taunts Batman by kidnapping and torturing Batgirl, which is decidedly not something you'd expect to find in a child-friendly version of this DC Comics property. Published in 1988, the original one-off comic book remains as polarizing as ever. Some claim it's the definitive Joker story. Though others have been quick to criticize it for being misogynistic. Warner Bros. Animation & Warner Digital Series' Sam Register had this to say in a statement to EW.

"From the start of production, we encouraged producer Bruce Timm and our team at Warner Bros. Animation to remain faithful to the original story, regardless of the eventual MPAA rating. The Killing Joke is revered by the fans, particularly for its blunt, often-shocking adult themes and situations. We felt it was our responsibility to present our core audience, the comics-loving community, with an animated film that authentically represented the tale they know all too well."

At this time, there are no plans to release The Killing Joke with a PG-13 edited cut. This latest Batman animated movie will have its world premiere at Comic-Con in San Diego this summer. A Blu-ray, DVD and VOD release is planned for later in the year.