The upcoming Arrowverse crossover "Crisis on Infinite Earths" will take a trip through the DC Multiverse. On top of featuring characters from all of The CW's superhero shows, it will also star plenty of guests from alternate Earths, such as Brandon Routh's Kingdom Come Superman, Smallville's Clark Kent and Lois Lane, and Kevin Conroy's aging Bruce Wayne. But on top of traveling across multiple realities, "Crisis on Infinite Earths" may also take fans on a trip through time, as DC's Legends of Tomorrow star Brandon Routh shared a couple of photos from the set of the crossover hinting at time travel.

On Instagram, the actor shared two pictures featuring himself as Ray Palmer, CEO of Palmer Technologies. "Traveled back in time on my birthday (yesterday) to a time before #RayPalmer knew #TimeTravel existed. 😉 #PalmerTech #CrisisOnInfiniteEarths," the actor wrote.

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It was previously theorized that time travel would factor into "Crisis on Infinite Earths" when set photos revealed Jonah Hex and Mia Smoak, who hail from the past and future, respectively, would share the screen with Barry Allen, John Constantine and Sara Lance. Routh's post only seems to give those theories more credence.

"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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