Well, it looks like the DC Extended Universe is official after all. To this point, the connected film universe based on DC Comics didn't really have an official name, especially since the post-Justice League franchise has focused more on individual stories rather than a shared narrative. It was dubbed the DC Extended Universe at some point and the name just stuck, though Warner Bros. never officially used it as a franchise label. That appears to have changed with the arrival of the HBO Max streaming service.
HBO Max, which is owned by WarnerMedia, launched in the United States on Wednesday morning, giving DC fans a place to watch all of the modern live-action DC films (save for the Christopher Nolan Batman trilogy, which will be available at a later date). There's a section of the service reserved for "Blockbuster Franchises", which can be found towards the bottom of the home screen. When you begin exploring that option, you'll see a list of live-action DC films labeled "DC Extended Universe."
The list of DCEU movies included on HBO Max consists of Batman v Superman: Dawn of Justice, Suicide Squad, Wonder Woman, Justice League, Aquaman, and Shazam!. You'll notice that Joker doesn't appear here, even though the film is on HBO Max, because it doesn't share any connective tissue with the other movies. It looks like the DCEU is strictly being kept to the films that stem from those Justice League continuity characters, which means that upcoming movies like The Batman, which stars Robert Pattinson, won't be included.
As it stands now, many of the future DC films do connect back to the Justice League story in one way or another. There are sequels to Aquaman, Wonder Woman, and Shazam! all in the works, as well as a follow-up to Suicide Squad (which features a few of the same characters). Really, The Batman is currently the only project that is exploring its own version of the DC Universe, though it could always be connected before all is said and done.
In addition to all of the existing DC content featured at launch, HBO Max will be the home for future theatrical releases from the franchise, as well as the infamous Justice League Snyder Cut. It was announced last week that director Zack Snyder and his post-production team would be going back to work and finishing his original vision for Justice League, which will be released exclusively on the HBO Max service in 2021.
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