Crisis on Infinite Earths is the name of the sixth Arrowverse crossover between Supergirl, Batwoman, The Flash, Arrow, and DC's Legends of Tomorrow. It began December 8 - December 10 and finished on January 14, 2020.
Synopsis
The "Crisis" event brings together the heroes from multiple Earths to battle against the Anti-Monitor, a godlike villain who threatens to destroy all reality.[1]