This year's Arrowverse crossover, "Elseworlds," has Barry Allen and Oliver Queen swapping lives, and costumes. The three-night event will also introduce Ruby Rose as Batwoman, and bring the heroes to a notorious Gotham City location, Arkham Asylum.
When an Arkham physician, John Deegan (played by Jeremy Davies), begins to rewrite reality, everything is turned upside down, and only Oliver and Barry realize something is awry.
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“You’re not going to see me playing Oliver Queen’s mannerisms, or Stephen [Amell] playing Barry’s mannerisms," Flash actor Grant Gustin told Entertainment Weekly. "It’s more being aware that for some reason we’ve switched lives and destinies."
Gustin considers the situation more of a goofy "situational comedy" than "a complete role reversal." Amell has to act out getting the hang of the Speed Force, while Gustin does more of the hand-to-hand combat we;re used to seeing on Arrow.
“The idea is that in order to be the best version of Barry Allen, which I have to be because we face a threat, there are elements of his personality I have to embrace," Amell said, "and there are elements of my personality that he has to embrace.”
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Other than more comedic in tone, "Elseworlds" also is going to be less cluttered. The Legends of Tomorrow cast will not be involved, and individual episodes will stand alone, as opposed to the feature-length plot that threaded together last year's "Crisis On Earth-X."
"Elseworlds" unfolds over three nights starting Sunday, Dec. 9, with an episode of Flash, and continuing Monday, Dec. 10, on Arrow before concluding Tuesday, Dec. 11, on Supergirl.