‘House Of The Dragon’ Star Milly Alcock Officially Casted as the DCU’s Supergirl

After weeks of rumors, we now have official confirmation from DC Studios head James Gunn regarding who he has casted for the DCU’s Supergirl.

When James Gunn revealed some of the projects that will usher in the DCU’s Chapter One: Gods & Monsters, one project that stood out in particular was the announcement of a Supergirl: Woman of Tomorrow film. The film, which is expected to be heavily influenced by Tom King’s acclaimed run with the character, hasn’t had major developments besides tapping Ana Nogueria as the scribe for the film. 

Recently, rumors have circulated that Supergirl will have a role in Gunn’s inaugural DCU film, Superman: Legacy, and we now have confirmation on who will play Kara Zor-El. Last night, Gunn confirmed on social media that Milly Alcock, best known for her work on HBO’s Game of Thrones spinoff House of the Dragon as Princess Rhaenyra Targaryen, will play the cousin of David Corenswet’s Superman

There was a slew of rumors this past week that Alcock and Meg Donnelly, who starred in Disney Channel’s hit musical franchise Zombies and who also voices Supergirl in recent DC animated movies (Legion of Superheroes; Justice League: Crisis on Infinite Earths Part One), both tested in Atlanta this past week for the role. 

While it is widely expected that Alcock’s Supergirl will make her debut in Superman: Legacy next year, Deadline notes that may not be the plan right now, and it is entirely possible that her debut may come in a separate DC project before taking center stage in Supergirl: Woman of Tomorrow. With Superman: Legacy expected to start filming in Atlanta in the Spring, we should get a pretty good idea of the DCU and its future very soon. 

Alcock’s Supergirl casting has mainly been praised by the fans, with Tom King (who penned the series with which this movie shares a name and premise) taking to social media to share his approval of Alcock’s casting. 

While King is thought to be part of the team of writers Gunn and Peter Safran have assembled to help shape the new DCU, it’s currently unknown what role, if any, he’ll play in this adaptation of the critically acclaimed comic book series, which saw Supergirl leave Earth to embark on an epic sci-fi adventure. Nevertheless, it appears that the dawn of the DCU is upon us. 

Superman: Legacy will be released in theaters on July 11, 2025.

What do you think of Milly Alcock being cast as the DCU’s Kara Zor-El? What DCU project do you believe Alcock’s Supergirl will debut in? As always, sound off in the comment section below, and tune in right here at The Cultured Nerd for the latest news surrounding James Gunn’s DCU.