James Gunn says he was interested in adapting Woman of Tomorrow with Milly Alcock as Supergirl even before deciding to take over as co-CEO of DC Studios

James Gunn already wanted to make a Supergirl movie before he took over DC Studios.

Speaking at a press event attended by GamesRadar+ to debut the first full trailer for the movie, Gunn revealed that he already had his eye on the graphic novel Woman of Tomorrow, and even thought Milly Alcock would be perfect for the role. Supergirl indeed stars Alcock as Kara Zor-El, with I, Tonya director Craig Gillespie at the helm.

"Why Supergirl? Why now? Why Craig? Why Milly? And the reasons are various, but the main one is when Ana Nogueira wrote the Woman of Tomorrow script, it was fantastic, and in DC Studios, we care most about the writing, and so we just instantly green lit the movie," Gunn shared.

"Now, it was something that I was very interested in making from before we even took over DC Studios," he continued. "I remember when the graphic novel first came out, when Peter [Safran, co-CEO] and I were kind of talking about taking over DC, but hadn't decided yet. I called Peter. I said, 'Have you seen this book by Tom King, Woman of Tomorrow?' I told him how great it was, what an interesting take it was on Supergirl. And I said, 'You know who would be great?' And I said – and I didn't know [Alcock's] name – I said, 'You see the little blonde girl on House of the Dragon? I think she would be great,' because it's sort of a rock and roll Supergirl, and that's why."

Alcock played young Rhaenyra Targaryen in House of the Dragon season 1, which was released back in 2022. She briefly reprised her role in season 2. Rhaenyra indeed was very headstrong and rebellious, so it's no surprise Alcock caught Gunn's attention.

"But then Milly, of course, had to audition with hundreds of other people, and she got the role," Gunn added. "Craig is one of my favorite directors, has been for a long time. He directed I, Tonya, which was my favorite movie from that year, but also many other movies that I enjoyed. And so when he threw his hat in the ring to direct this film, we were more than interested. And now, here we are."

Supergirl arrives in theaters on June 26, 2026. In the meantime, see what else DC has in store with our guide to all the upcoming DC movies and shows.