CW Arrowverse Crossovers

Crisis on Infinite Earths: Part 1 (Supergirl) (6x1)

Air date: Dec 08, 2019

The Monitor sends Harbinger to gather the worlds' greatest heroes -- Supergirl, The Flash, Green Arrow, Batwoman, White Canary, The Atom, and Superman -- in preparation for the impending Crisis; Lena must find a way to save the people of Earth-38.