Supergirl: Survivors

"Survivors" is the fourth episode of season two of the spuerhero fantasy series Supergirl, and the twenty-first episode of the series overall. It was directed by Glen Winter with a teleplay written by Andrew Kreisberg and Jessica Queller based on a story treatment by Greg Berlanti and Andrew Kreisberg. It first aired on the CW Network on Monday, October 31st, 2016.