Pariah enlists Black Lightning to help stop the Anti-Monitor after Flash-90 shares what he learned from his battle in ‘Elseworlds.’ With the help of Black Lightning, Barry, Cisco and Killer Frost come up with a plan that could save them all. Meanwhile, Iris has a heart-to-heart with Ryan Choi, while Oliver and Diggle return to an old familiar stomping ground.

This crossover begins with Supergirl S05E09 and Batwoman S01E09, and continues on Arrow S08E08 and Legends of Tomorrow’s special episode.