While the rest of the Arrowverse is already halfway through their respective seasons, Legends of Tomorrow's fifth season has not even begun. Turns out, the new season can't begin until "Crisis on Infinite Earths" is resolved.
“'Crisis' is essentially a prequel to [Legends of Tomorrow] Season 5,” showrunner Keto Shimizu told CBR. As such, the events of "Criss" will be a major story driver for Legends when it returns.
This made production tricky. Shooting for Legends began before "Crisis," which meant the writers had to know what happened after "Crisis" before the were able to plan "Crisis."
“However, it was shot out of order, so we have to know the sequel to everything that was going to happen in 'Crisis' before we had even written 'Crisis,'" she said. "So that was very tricky for us.”
"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.
Returning on Jan. 21, 2020, 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.