|Season 3, Episode 11|
|Brave New World||Supergirl Reborn|
ALEX AND MAGGIE TAKE A BIG STEP- Maggie spends her day off scouring National City for the "perfect ring" for Alex. Meanwhile, Alex takes to the streets with her own brand of vigilante justice. Lena asks Eliza to accompany her to a fundraiser. On New Krypton, Kal challenges Zod's authority, and Alura gives Kara an ultimatum: embrace her Kryptonian heritage or be banished to Earth. Savage draws the suspicions of Astra and Non.
- Melissa Benoist as Kara Danvers/Supergirl/Kara Schott
- Chyler Leigh as Alex Danvers/Batwoman
- Jeremy Jordan as Winn Schott (Earth-6)
- Katie McGrath as Lena Luthor
- Laura Benanti as Alura Zor-El & Astra In-Ze
- Tyler Hoechlin as Kal-El
- Floriana Lima as Maggie Danvers
- Zachary Quinto as General Dru-Zod
- Odette Annable as Samantha Arias/Reign
- Jenna Dewan as Lucy Lane
- with Claire Holt as Karen Starr/Power Girl
- and David Harewood as J'onn J'onzz
Special Guest StarsEdit
- Harry Lennix as Commander Fer-Gor
- Chris Vance as Non
- Tracy Spiridakos as Lesla-Lar
- Dianna Agron as Raya Zod-El
- Paige Turco as Lara Lor-Van
- Casper Crump as Vandal Savage
- Amy Jackson as Imra Ardeen
- Georgina Campbell as Lieutenant Asha Del-Nar
- Jesse Rath as Brainiac 5
- Chad Lowe as Thomas Coville
- Andrea Brooks as Eve Teschmacher
- Emma Tremblay as Ruby Arias
- Robert Gant as Zor-El (flashbacks)
- Wallis Day as Nyssa-Vex
- Genevieve Buechner as Young Alura Zor-El (flashbacks)
- Alessandra Torresani as Young Jindah Kol Rozz (flashbacks)
- Antagonist: None
- 7th episode this season to feature all main characters.
- Alex begins her brief tenure as Batwoman.
- First appearance of Brainiac 5.
- This episode is Maggie-centric.
- This episode is concurrent with Brave New World.