5x17 — Supergirl

: The episode features the return of M'gann M'orzz, who joins J'onn and Kara to battle a Sun-Eater .

: The episode uncovers Lex's role in the death of Jeremiah Danvers, which he framed to manipulate Eve Teschmacher into his service. Notable Details

: The story was written by Lindsay Sturman, with a teleplay by Katie Rose Rogers and Brooke Pohl. Supergirl 5x17

: Lex pits Supergirl and her team against the secret organization Leviathan, all while positioning himself to defeat them and appear as the hero.

: Lex meticulously orchestrates events to drive Lena Luthor closer to him while furthering her rift with Kara. : The episode features the return of M'gann

The seventeenth episode of 's fifth season is titled " Deus Lex Machina " . This landmark episode marked the directorial debut of the series star, Melissa Benoist. Key Plot Developments

: It reveals how Lex manipulated the new reality to become a Nobel Peace Prize winner and a beloved public figure. : Lex pits Supergirl and her team against

Watch the official sneak peek for this episode, featuring Melissa Benoist's directorial work: