The Swarm
Season 3, Episode 18
Vital statistics
Air date Unaired
Written by Illyriarocks
Directed by Illyriarocks
Episode guide
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Nova Day The House of Zod
The Swarm is the eighteenth episode of Supergirl Season 3 and the 60th episode overall. It is the third part of the 5-part TRIAL storyline, focusing on the political strife on New Krypton.


ALEX TAKES COMMAND OF EARTH'S DEFENSE- When J'onn is incapacitated, Alex steps up as interim director of the DEO when Brainiac attacks Earth, ultimately learning the hard way that the Phantom Zone still exists. On New Krypton, Lara and Savage work to save the lives of Dru-Zod, Kal, and Karen while Kara and Astra pursue Ral-Dar.

Main CastEdit

Special Guest StarsEdit

Recurring CastEdit



  • Antagonists: Brainiac, Sam Lane, Lex Luthor
  • This episode is Alex-centric.
  • 8th episode this season to feature all main characters.
  • James was last seen in Brave Enough.
  • Krull was last seen in Fight or Flight.