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The Legends of Tomorrow might not return with Season 5 until the year 2020, but they will be a part of the Arrowverse’s next crossover.

The CW president Mark Pedowitz announced on Thursday at the network’s Upfront presentation that the “Crisis on Infinite Earths” team-up event will be told in five parts over two quarters — meaning, it will start in December and then conclude early in the new year, following the midseason break.

TVLine has since confirmed with sources that the five shows taking part in the crossover will be Arrow, The Flash, Supergirl, Batwoman (which premieres this fall) and Legends. Three of the five parts will air in December, and the other two — including an episode of Legends, which this year premieres at midseason — will follow in early 2020. (It is unclear at this time what the second show airing its crossover episode in the new year will be.)

Arrow and The Flash with their season finales this past week each planted massive Easter eggs related to the crossover. The Monitor from the “Elseworlds” crossover showed up on Arrow to collect on the deal he made with Oliver, pulling him away from wife/new mom Felicity for a mysterious mission. The Flash’s finale-ending tag, meanwhile, showed that the ominous “crisis” in which Barry is destined to vanish has been moved up from 2024 to 2019, due to a time flux.

And the teases aren’t done coming. Sources tell TVLine that Supergirl’s own season finale, airing this Sunday at 8/7c, will drop its own clue about the crossover, and it’s one viewers won’t want to miss. (What do you it will be??)

“Crisis on Infinite Earths” will be “the biggest and most complicated [crossover yet],” The CW’s Pedowitz previously avowed. “I can’t tell you if it’ll follow the comic book version, but it’ll take some big swings.”

“It is ‘Crisis on Infinite Earths,’” he added, “and if you know the history, things collapse.”

Want scoop on any of the above shows? Email InsideLine@tvline.com and your question may be answered via Matt’s Inside Line.