The Arrowverse is back, and this year, it brings with it the biggest crossover event yet for the DCTV universe. 'Crisis On Earth X' is going to bring together all four shows (Arrow, The Flash, Supergirl and Legends of Tomorrow) for a 'four hour movie' style event, where each episode connects completely to the others. This is an expansion of the usual crossover style for the CW's comic universe, where heroes from each show make an appearance in each other's episodes.The crossover also promises plenty of opportunities for the Arrowverse to include a few new dopplegangers - or even entirely new versions of characters. Some fans are even wondering if the 'Crisis' in the title heralds a 'Crisis On Infinite Earths'-style simplifying of the Arrowverse, where all four shows will be brought together into a single universe... potentially including a familiar face f rom the older DC series, Smallville.

What Is Crisis On Earth X?

While the CW is keeping the details of the crossover close to their chest for now, there's quite a bit that we know about Earth-X already. One of the many different worlds in the DC multiverse, Earth-X explores what the world would look like if Hitler had been successful and managed to take over the entire world. While there are pockets of resistence, led by the super-team Freedom Fighters, the majority of superheroes we know and love work on behalf of the Nazi regime to continue the oppression of the people of Earth.

The crossover event itself will take place as Barry Allen (Grant Gustin) and Iris West (Candice Patton) finally get married (or try to, anyway). It will pit each of the Arrowverse heroes against their evil Nazi counterparts (Dark Arrow, Dark Flash, and Overgirl), as well as Earth-X versions of various other Arrowverse villains. It's a story that will revolve around Oliver (Stephen Amell), but that will have a huge impact on the Arrowverse as a whole.

Will Evil Superman Make An Appearance?

Supergirl season 2 finale - Evil Superman

While the poster for the event has confirmed that 'Dark' versions of the Arrowverse big three (Supergirl, The Flash, and Green Arrow) will all be appearing on Earth-X, they aren't going to be the only ones with evil dopplegangers. We can presumably expect to see some Earth-X versions of the Legends and the other members of Team Flash, Team Arrow, and Team Supergirl - whether they will still be on those same teams or not.

Previous doppleganger universes have included versions of characters who are not superheroes, who are different heroes, or who are different villains. From Black Siren (Katie Cassidy) to Jay Garrick (John Wesley Shipp), there have been plenty of dopplegangers who range from an 'evil' version to a totally different character, and this is sure to happen on Earth-X as well. Which begs the question: is there going to be an Earth-X Superman in the mix?

In the comics, Superman is very much a part of this alternate universe, as one of the leaders of the Gerechtkeitliga, aka the Justice League Axis. He's one of the 'heroes turned evil' at the core of this universe, and an opponent to the Freedom Fighters who continue to resist. As Superman (Tyler Hoechlin) has already appeared in the DCTV universe, it would be very possible for him to return for the crossover event, although this hasn't been confirmed yet.

Tom Welling Wants To Return To DC

Tom Welling Superman CW Arrowverse

The possibility of an alternate Superman has sparking speculation that this might be the role that brings Tom Welling back to the CW's DC universe, as the Superman of Earth X. Welling first appeared in the DC live action world as the star of Smallville, an earlier superhero offering from the CW that ran for ten seasons and told the story of Clark Kent from high school teen to the Superman that we know and love.

Welling has recently commented that he would love to be a part of the DCTV universe, saying that he already has some ideas about how he could appear on The Flash. Many fans had hoped that Welling would reprise his role as Superman on Supergirl, so this would be a second option to see the actor back in red and blue for a few episodes. Adding Welling as Superman on an alternate Earth would be a great way to include the actor, and one that would allow for guest appearances in future, without committing him to a regular part. It would also be great to see another Smallville alum appear as an Arrowverse villain, as Laura Vandervoort did last year when she popped up on Supergirl as Indigo. It's even possible that a Crisis storyline involving multiple earths could include the Smallville universe as another alternate reality - something that would certainly make Smallville fans happy, but that would be more than a little complicated to pull off.

Tyler Hoechlin as Superman in Supergirl

Welling Vs Hoechlin

Of course, the introduction of Welling as the Earth-X Superman is not without problems - the main one being that the Arrowverse loves to deal in dopplegangers. The Dark versions of the other characters that will be appearing on Earth-X are played by the same actors as their counterparts in the main universe - and it follows that Superman would likewise be identical in appearance to the Superman in Supergirl. This would mean that should Superman appear on Earth-X, he would be played by Tyler Hoechlin.

Hoechlin is already a fan-favorite on the show, even though he has only dropped in a few times to help out his cousin. He's also already become an evil version of himself, when he was poisoned with silver kryptonite during the Daxamite invasion. If evil-Superman appears on Earth-X, it would be far more likely that he would be played by Hoechlin, rather than Welling.

Of course, this isn't a guarantee, as the Flash of Earth-2 is not a doppleganger of Barry Allen, and alternate universes can come with some big surprises, but it's still the biggest roadblock to Welling appearing on Earth-X.

Welling's Other Options

Tom Welling as Marcus Pierce in Lucifer

While fans of Smallville would love to see Welling reappear in the Arrowverse as Superman, and Earth-X would be an easy way to do that, it's not the only option. Welling's comments are only that he would like to make an appearance on the show, not that he will only do it if he can play the same character.

It's possible that Welling may join the Arrowverse as another universe's Superman, or even the Superman of Earth-1 (which is not a doppleganger version of the Supergirl universe, so could well include a Superman played by a different actor). It's also very likely that he will appear as a different character altogether, with a few nods to the fans that acknowledge his previous role. The Arrowverse has already done this with Dean Cain, who plays Kara's foster father in Supergirl, or Linda Carter, who plays the President of that United States. There has been no official news on either Earth-X Superman or on the possibility of Welling guest-starring in the Arrowverse, so for now, it's all speculation - and fans looking forward to the crossover event in November!

œCrisis on Earth X takes place across two nights on Monday, November 27 and Tuesday, November 28 on The CW. Supergirl and Arrow will air on Monday and The Flash and Legends of Tomorrow will air on Tuesday.

Next: The Arrowverse Earth-X Crossover Explained

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