Medusa

When the Danvers celebrate Thanksgiving, Alex tries to find the right time to tell her mother Eliza that she's gay. Meanwhile, Lena is forced to choose when Supergirl tells her that Lillian plans to unleash a virus that will wipe out every alien in the city. Crossover among four CW shows: Supergirl "Medusa"; The Flash "Invasion!"; Arrow ‘Invasion!"; DC's Legends of Tomorrow "Invasion!"

Where to watch

▶ Netflix

• Prime Video to buy

Where to watch from the Streaming Availability API by Movie of the Night.

Still and episode from TVmaze.