Milly Alcock has been cast as Supergirl in James Gunn and Peter Safran’s new DC Universe.

The Australian actress, who is best known for playing young Rhaenyra Targaryen in the Game of Thrones spin-off House of the Dragon, has landed the coveted role of the Woman of Steel.

She will lead Supergirl: Woman of Tomorrow, based on the DC Comics run of the same name by Tom King and Bilquis Evely.

Director James Gunn, the co-head of DC Studios, confirmed the news on Instagram.

“This is accurate. Milly is a fantastically talented young actor, and I’m incredibly excited about her being a part of the DCU,” he wrote. “Yes, I first became aware of her in House of the Dragon but I was blown away by her varied auditions and screen tests for #Supergirl. She embodies Kara as envisioned by (comic creators) @tomking_tk, @bilquis and (screenwriter) Ana Nogueira.”

Nogueira was hired to write the screenplay for Supergirl: Woman of Tomorrow in November but the project does not yet have a director.

It is unclear when Alcock, 23, will make her debut as the superhero, who is Superman’s cousin. It has been rumoured that she will make an appearance in Superman: Legacy, which is about to begin shooting, before headlining her own film.

Gunn is directing Superman: Legacy, the first film in the new DC Universe, from his own screenplay. It will star David Corenswet as Clark Kent/Superman and Rachel Brosnahan as Lois Lane and be released in cinemas in July 2025.

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