Crisis on Earth-X, Part 4

"Crisis on Earth-X, Part 4" is the upcoming eighth episode of the third season of DC's Legends of Tomorrow, and the forty-first episode overall. The episode is the third of a four-part crossover with the eighth episode of the third season of Supergirl, eighth episode of the sixth season of Arrow and eighth episode of the fourth season of The Flash. It will air on November 28, 2017.