Everything We Know About the Arrowverse "Elseworlds" Crossover

Every year we're treated to the crossover event of the season when The CW's greatest heroes unite to punch Nazis, time travel and take down aliens -- sometimes all in the same night! This year,Arrow, SupergirlandThe Flash will have a three-night crossover (DC's Legends of Tomorrow will sadly not participate this time), and while most plot information is being kept tightly under wraps, we've been able to pick up quiet a few details here and there. Behind-the-scenes photos, posters and casting news have created a hazy picture of what's to come if you look closely enough. Here's everything we know so far about the epic 2018 Arrowverse crossover event!

The crossover begins Sunday, Dec. 9 at 8/7c, but it won't start with Supergirl. For one week only, Supergirl and The Flash are trading time slots, so double check your DVRs! The Flash will kick off the three-part crossover on Sunday, Dec. 9, with Arrow following on Monday, Dec. 10, and Supergirl finishing things off on Tuesday, Dec. 11.

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It's titled "Elseworlds." There hasn't been an official statement revealing what this title means, but it's pretty clear from everything we've seen so far that it will show us alternate histories or realities where our characters are living very different lives. The DC Comics imprint called Elseworlds depicted Batman in the Victorian Age hunting down Jack the Ripper, for example.

Oliver (Stephen Amell) and Barry (Grant Gustin) are swapping places or bodies? A poster for the Elseworlds crossover shows Barry dressed as the Green Arrow while Oliver's sporting Barry's new, red speedster suit. As if that wasn't weird enough, Amell and Gustin also posted behind-the-scenes photos of themselves wearing matching biker costumes (complete with bandanas, gloves and studded boots), creating more speculation about what kind of switcheroo these two will be pulling.

The first teaser features a confused Oliver kissing Iris, who calls him Barry Allen. So all of this tracks.

Batwoman will make her first appearance. This summer, The CW revealed that Batwoman would make her debut in the Arrowverse crossover, and she'd be played by none other than Ruby Rose. Our first look at Rose in character can be summed up in one word: badass.

A lot more DC characters are showing up! Superman (Tyler Hoechlin) is returning, but Lois Lane (Grimm's Elizabeth Tulloch), Mrs. Freeze (Cassandra Jean Amell) and The Monitor (LaMonica Garrett) will pop up too! Posters for the crossover even have us theorizing that Anti-Monitor will make an appearance. Hoechlin was actually spotted in a behind-the-scenes photo sporting an all black version of his super suit, lending credence to the theory that we'll be seeing a different version of Superman than the one we're used to.

What Does the Arrowverse Crossover Title "Elseworlds" Mean?

We will be visiting the Kent Farm. Melissa Benoist shared a cute photo of her, Hoechlin and Tulloch at what appears to be a ranch or farm. She captioned the photo, "two kryptonians and a journalist walk into a crossover." Amell tweeted a photo of a similar site, captioning it, "Elseworlds." Stephen Amell also teased that we'll be getting an awesome Smallville reference in this year's crossover.

Prepare for an iconic comic book moment. Hartley Sawyer told TV Guide that a scene he watched being filmed for the crossover pleased his inner comic book nerd so much that his hair actually stood up on end. "What I was watching and the image that I saw -- and I took a picture on my phone -- even now my hair is starting to stand up," Sawyer said. "I grew up reading comic books. I grew up watching the Tim Burton movies, the Christopher Reeves Superman, all that stuff. It was something that I wanted when I was 5-years-old so, so badly, and now it's real. And I think people are going to just lose their minds when they see this. It was just this one image in this whole -- ugh, it's going to be incredible."

John Wesley Shipp will return: Stephen Amell tweeted another photo of himself, Benoist and Gustin filming a scene with John Wesley Shipp, who played Henry Allen in the first two seasons of The Flash before playing Earth-2 Jay Garrick. By the looks of the photo, Shipp returns as Garrick in a Flash suit that is reminiscent of his old suit from CBS' The Flash series from the '90s.

The Arrowverse crossover event kicks off Sunday, Dec. 9 at 8/7c on The CW.

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