Ever since the DC Universe Original animated series kicked off with Justice League War in 2014, the Blu-ray and DVD always includes a preview of the next movie that will be released. The latest from this franchise is Batman: The Killing Joke, which had its world premiere screening at San Diego Comic-Con last weekend, where it was confirmed that the next animated movie will be Justice League Dark. Although it isn't known when this exciting animated advengure may debut. Now that Batman: The Killing Joke is available on VOD platforms, ahead of the Blu-ray and DVD release on August 12, the eight-minute sneak peek of Justice League Dark has already leaked online.

It was confirmed at Comic-Con that Justice League Dark, an adaptation of the popular comic book series, will bring John Constantine to the world of animation for the first time in a supernatural story that promises plenty of mystery and thrills, along with an amazing voice cast. While Constantine's world of demons and magic are an important part of the DC Universe, it's been largely unexplored in DC's connected universe of animated movies until now. Justice League Dark was originally being conceived as a live-action movie with director Guillermo del Toro, but now they will adapt this story as an animated movie only.

This video, which surfaced on YouTube earlier today, confirmed that Matt Ryan, who starred on NBC's short-lived Constantine TV series, will provide the voice of John Constantine. The voice cast will also include Jason O'Mara as Batman, Camilla Luddington as Zatanna, Nicholas Turturro voices Boston Brand and Ray Chase voices Etrigan. DC Entertainment's Mike Carlin confirms in this video that other characters include Deadman, Swamp Thing, Black Orchid, but we don't know who will voice these characters just yet.

Related: Justice League Dark Trailer Teams Batman with Constantine & Swamp Thing

We also hear from some of the voice actors themselves, with Matt Ryan revealing he wanted to portray John Constantine in a different context, while Jason O'Mara reveals that he thinks it's one of the best Justice League animated scripts he's read so far. This video also includes plenty of insight on this story from director Jay Oliva and producer James Tucker, along with a slew of footage. The end of this video teases that the movie will be available sometime this fall on VOD, Blu-ray and DVD formats.

It was also announced at Comic-Con that the next two movies after Justice League Dark will be Teen Titans: The Judas Contract and Batman and Harley Quinn. No release dates were given for either of these movies, and it wasn't announced who will write, direct or lend their voices to these projects. While we wait for more details, check out this first look at Justice League Dark, and stay tuned for more on this animated movie.