Supergirl season 3 episode 10
Episode title: Legion of Superheroes
Struggling to heal from her injuries inflicted by Reign, Supergirl remains in a dreamlike state, unable to be reached. Mon-El recruits one of the Legion members, Brainiac-5, to try to bring her back. Meanwhile, Reign continues her rampage on the city so the DEO teams up with the Legion of Superheroes to try to stop her.
