|Season 7, Episode 10|
|DNR||Off With Her Head|
PART 3: COME TO CLEANSE- Reign leads her cult in a final battle against The Last Children of Krypton and their allies. As National City crumbles around them, Kara Danvers makes a rash decision and Susannah Russo imparts life-changing news to Alex Danvers.
- Melissa Benoist as Kara Danvers/Supergirl
- Chyler Leigh as Alex Danvers
- Katie McGrath as Lena Luthor
- Odette Annable as Reign/Samantha Arias
- Tyler Hoechlin as Clark Kent
- Olivia Wilde as Susannah Russo
- Jenna Dewan as Lucy Lane/Superwoman
- Minka Kelly as Dawn Granger
- Claire Holt as Karen Starr/Power Girl
- Michael Rosenbaum as LX-52
- Emmy Rossum as Zaora Dru-Zod
- with David Harewood as J'onn J'onzz/Martian Manhunter
- and Mehcad Brooks as James Olsen
- Emmanuelle Chriqui as Sarah Essen
- Rachel Nichols as Slam Bradley
- Brit Morgan as Livewire
- Brenda Strong as Lillian Luthor
- Daniel Sharman as General Lor-Zod
- Tamzin Merchant as Lyra Strayd
- Teressa Liane as Mary Louise Fairchild
- Scarlett Byrne as Nora Fairchild
- Lili Reinhart as Aethryr
- with Oded Fehr as Ra's al Ghul
- and Dichen Lachman as Talia al Ghul (Earth-27)
- and Alexandra Daddario as Cameron Chase
- Antagonist: Reign
- 3rd episode this season to feature all main characters.
- This episode is Alex-centric.
- This episode takes place on May 23, 2023.