For actors, casting usually works something like this: hear about a role from agent, audition, second audition, chemistry check, another audition, repeat as necessary.
However, fans are now speculating that actor Milly Alcock got to skip a few of those steps in the process of being cast as the titular character in Supergirl, an upcoming project by director James Gunn for DC Comics.
Supergirl (2026) will follow Kara—the name of the character—in a galaxy-wide revenge quest with recent Old Guard 2 actor Matthias Schoenaerts as the villain Krem of the Yellow Hills. Production began on the film in early 2025. The film is part of the DC Universe's arc of films "Chapter One: Gods and Monsters."
Alcock, a 25-year-old Australian actress, starred as young Rhaenyra Targaryen in the HBO fantasy series House of the Dragon, for which she was nominated for a Critics' Choice Television Award for Best Supporting Actress in a Drama Series.
At the 2023 Golden Globes, House of the Dragon won Best Drama Series. When Alcock was onstage with Emma D’Arcy and ex-co-showrunner Miguel Sapochnik, she couldn’t stop giggling and was noticeably glassy-eyed.
After a clip of her appearance went viral, she told Jimmy Kimmel:
"You know, I enjoyed the free champagne. Clearly."
Since the character of Supergirl is plucky but also quite messy, fans suspect that Gunn saw the awards and immediately thought, "I have to cast her."
It's just a theory, but a funny one that is making the rounds on social media nevertheless.
People ran with the theory.
If it wasn't an audition, maybe she was preparing for the role?
Kara (Supergirl) will be similar to Milly in character, so this was probably more like a sneak peak.
People joked that her casting was pretty much a done-deal after the Golden Globes.
Gunn's vision for Supergirl is very distinct from Superman.
Supergirl is set to come out in 2026, although Alcock can be seen in a scene in Superman, out now in theaters.
