CW's upcoming "Crisis on Infinite Earths" crossover could bring continuity changes big and small to the Arrowverse.
According to Rolling Stone, showrunner Marc Guggenheim relayed to the creatives of the various Arrowverse shows that "Crisis on Infinite Earths" is "a magic ticket," allowing them to make major and minor continuity changes in much the same way as the comic book event on which the crossover is based.
Created by Marv Wolfman and George Perez, the 12-issue Crisis on Infinite Earths limited series ran from 1985 until 1986. The book was envisioned as a way to unite the DC Multiverse into a single DC Universe, effectively streamlining the continuity in the process. This meant that the backstories of various heroes and villains were altered to account for the new continuity.
"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.