Behind-the-scenes photos from the filming of the Earth-X crossover event confirm that Reverse Flash is back. The Flash fans are loving the return of the fastest man alive, and they're looking forward to the big event of the Arrowverse this season: a massive Earth-X crossover event that will bring together Arrow, The Flash, Legends of Tomorrowand Supergirl in a four hour special over two nights. The crossover event is set to air next month, and has been filming this week, leading to some interesting set photos making headlines, including one of Nazi Supergirl (or Overgirl) herself.

Now, another set photo has surfaced from the filming of the crossover event, and it reveals something that fans have suspected since the poster for the event was released: the identity of the Earth-X Flash. While the promo material for the event showed a the familiar yellow of the Reverse Flash's costume, it wasn't clear whether or not this would be a Barry Allen (Grant Gustin) version of the character or not, but now we know for sure.

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The photos, posted by Themyscira Bound on Twitter, show Tom Cavanagh wearing the Reverse Flash suit, with the hood pulled down away from his face. The suit matches that of the Earth-X Flash on the poster, with the yellow chest turning into a black suit below the waist. The images also show Grant Gustin in his red Flash costume walking next to Cavanagh (wearing only part of his costume).

Guess who's back?! #TheFlash #ReverseFlash #LegendsOfTomorrow #crossover @WhatsFilming @yvrshoots @olv @CavanaghTom pic.twitter.com/48r8Ijo8av— Suffering Sappho (@ThemysciraBound) October 17, 2017

The Reverse Flash costume matches that of the comic book Earth-X Flash, but it wasn't known until now whether or not the Arrowverse Earth-X would be played by Grant Gustin or someone else. The Earth-X Supergirl (Overgirl) is being played by Melissa Benoist, suggesting that at least some of the heroes will have evil doppelgangers in this crossover. Of course, now that we know that Cavanagh is going to be the Earth-X Flash, it seems that not all the evil counterparts of the Arrowverse heroes will be duplicates.

Harrison Wells was, of course, the Reverse Flash of Earth-1 in earlier seasons of the Flash, before it was revealed that Reverse Flash was actually Eobard Thawne (Matt Letscher) pretending to be Harrison Wells who was the speedster villain. It's not yet clear how this will play into the Earth-X Reverse Flash's identity, and whether this will also be Thawne-as-Wells, or if this is the true Harrison Wells' identity in this alternate universe.

Whatever the details, fans will be thrilled to see Cavanagh return to the show, as he (in all his many character guises) has been a fan favorite from the beginning. We'll keep you up to date with more news on how, exactly, he fits in.

Next: The Flash Drops MAJOR Justice League Easter Egg

The Flash continues Tuesday, Oct 24th with ‘Luck Be A Lady’ on The CW.

Source: Themyscira Bound (Twitter)