We've known since July that DC’s Legends of Tomorrow won't participate in this year's Arrowverse crossover, “Elseworlds." However, the same week as the December event, the CW series will stage its own crossover, of sorts.

“During the week that all the other crossovers are happening, we will essentially be crossing over with ourselves," showrunner Keto Shimizu told TV Line, explaining the special episode will take the Legends across “alternate time periods.”

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“That particular episode is insane,” star Caity Lotz added. “I think they wanted to do something special since we weren’t going to be doing the ['Elseworlds'] crossovers.” Dropping another clue, she added, “You’ll see a lot of different sides of the Legends.”

“I’ll just say it’s a lot of work for the people who are in those scenes,” star Tala Ashe said. “It’s fun.”

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That would seem to suggest the characters will interact with alternate versions of themselves, not dissimilar to what happened in the Season 2 finale, involving the Spear of Destiny.

Returning to The CW on Monday, Oct. 22 at 9 p.m. ET/PT, DC’s Legends of Tomorrow stars Caity Lotz, Dominic Purcell, Brandon Routh, Nick Zano, Maisie Richardson-Sellers, Tala Ashe, Matt Ryan, Jes Macallan and Courtney Ford.