Before we get to the new universe, we have to reboot away the old one. Or, in this case, several old ones as the current "Prime" continuity for this film is really an amalgamation of various versions of DC continuity that's come before. And then Flash goes back in time and ruins everything.
Now in a fresh, New 52-inspired continuity, we pick up with our favorite, familiar heroes as they set off on their first adventure together, a battle against the evil supervillain, Darkseid. Earth is doomed.
Introducing another new hero for the league, this movie gives us Arthur Curry, aka Aquaman, four years before a similar adventure would come out on the big screen.
Damien Wayne doesn't play well with others, a trait his father would like to see changed. So he's put on a team with other supepr-powered teens to see if they can work together for once. Probably not, though.
A magical threat pushes its way across the Earth, so Batman has to team with an expert in magic: John Constantine. It's time to form a new faction of the League.
When a movie has a title like this, I think we all know what's coming. Based on the comic series of the same name, this film is only going to end one way, and it won't go well for our titular character.
After the relative success of Man of Steel (a film that made good money but didn't seem to really have the backing of critics or fans), DC followed it up with a semi-sequel, semi-crossover, putting in the only character in comics arguably bigger than Superman: the Batman. Sadly, the results were just not good.
The production of Justice League was troubled, with original director Zack Snyder leaving part way in (for family reasons) and Joss Wheddon coming in to do extensive rewrites and re-edits. Although the final film is watchable, it's still not great in comparison to the filmic output of Marvel.
While assisting Superman defend Metropolis, the Flash gets sucked into the past (he thinks), forced to help a team of heroes all the way back in World War II.
It's time for a retro adventure as the Justice League goes back to the 1950s era to take on an evil new threat, the Center.
Young Justice
The young heroes of the Justice League, wanting to strike out on their own and not be "side-kicks" any longer, a put together on a new team to show just who they can be.
Superman suffers a terrible loss and suddenly decides its time to clean up the world, and the Justice League is split over what to do in this gory superhero tale.
Johnathan Kent and Damien Wayne are not the best of friends, but the two will have to team up when a powerful alien being attempts to take over the planet.
The teen heronies have to battle a threat to their world from an ancient Kryptonian evil, and also the Teen Titans are here for some reason, in this weak crossover film.
The Justice League gets sucked into the world of Remnant where they work with the team of RWBY to try and figure out how they got there and why the world seems so wrong.
See Also
DC FanDome 2021: A look at the upcoming projects for DC Comics in 2021 and 2022
Canceled DCEU Projects: With the death and rebirth of the DCEU actively going on, we take a look back at all the projects that could have been (and likely never will).