The CW's upcoming Arrowverse crossover will span 5 nights. Here's everything you need to know.

The CW's upcoming Arrowverse crossover will span across five nights, beginning on Monday, December 9 and concluding on Tuesday, January 14. The event, titled "Crisis on Infinite Earths," will include characters from "Arrow," "The Flash," "Supergirl," "Legends of Tomorrow," "Batwoman," and "Black Lightning." "Smallville" stars Tom Welling (Clark Kent) and Erica Durance (Lois Lane) will also make appearances. Visit Insider's homepage for more stories. The Arrowverse's upcoming crossover, "Crisis o...