Arrowverse executive producer Marc Guggenheim has shared a new look at the upcoming "Crisis on Infinite Earths," with an image that possibly comes from the opening title card for The CW crossover event.Guggenheim shared the image on Twitter with the caption, "A glimpse from #CrisisOnInfiniteEarths because it's Thursday."RELATED: Crisis on Infinite Earths' Anti-Monitor Debuts in New ImageThe image features the tip of a Green Arrow arrowhead, a bright blue streak of light -- possibly Supergirl flying at top speed -- and the yellow-and-red lightning bolts of The Flash.

"Crisis on Infinite Earths" has a star-studded list of guest stars. Batman: The Animated Series star Kevin Conroy, Black Lightning's Cress Williams, Batman 1966 star Burt Ward, Legends of Tomorrow's Jonah Hex, The Flash triple-threat John Wesley Shipp, Birds of Prey alum Ashley Scott and Smallville's Tom Welling and Erica Durance, as well as "Elseworlds" alums Tyler Hoechlin and Elizabeth Tulloch, are among those appearing the crossover. DC's Legends of Tomorrow star Brandon Routh has been confirmed to appear as Kingdom Come Superman.

"Crisis on Infinite Earths" begins Sunday, Dec. 8 at 8 p.m. ET/PT on Supergirl, then continues in Batwoman on Monday, Dec. 9 at 8 p.m. ET/PT and in The Flash on Tuesday, Dec. 10 at 8 p.m. ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.

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