James Gunn loved Milly Alcock's "edge" in House of the Dragon, and that makes me very excited for the DCU's version of Supergirl

James Gunn has continued his impressive casting streak with the announcement that Milly Alcock is the new Supergirl. The Australian actor, best known for her roles in House of the Dragon and Upright, is officially Kara Zor-El, joining actors like David Corenswet as Superman and Nicolas Hoult as Lex Luthor in the new DCU.

The early reports are that her screen test was fantastic, which helped land her the part over other stars like Meg Donnelly and Emilia Jones, but there’s something else about this announcement that has me very excited. 

Posting on Threads following the news of her casting, Gunn explained that Alcock was the first person he brought up in a conversation with his DC Studios co-CEO Peter Safran. "Well over a year ago, when I had only read the comics,” he explains, “I was watching House of the Dragon & thought she might have the edge, grace, and authenticity we needed for the DCU’s Supergirl. And now here we are. Life is wild sometimes."

Now, this is interesting. The fact that it was Alcock’s performance as Rhaenyra Targaryen in the Game of Thrones prequel that got her in the door feels like a pretty great omen of what’s to come in the DCU. This is especially true as it seems it wasn’t just her prowess as a brilliant actor, but there was something in the charisma and darkness of that character that screamed Supergirl to Gunn.

Scene stealer

For me, there’s little doubt that Alcock’s performance as Rhaenyra in House of the Dragon’s opening episodes was one of the main reasons the show became the success it was. The series had a lot working against it, falling as the first Game of Thrones spin-off since the much-maligned season 8 and telling a more ambitious time-skipping story than the slow-paced original was used to. 

But as a tenacious, inquisitive, and easily-influenced young princess who is thrown into the world of conniving and power-hungry men, Alcock navigates the storytelling perfectly. She’s just as believable as a young teen vying for the attention of her uncle as she is as a young woman suddenly aware of the power she holds by the benefit of her name.

She also has magnetic chemistry with everyone she shares the screen with. Her scenes with Matt Smith’s Daemon are of course the stand-out as she goes toe-to-toe with an actor well-known to audiences, and comes out the victor of their vicious exchanges. Equally her scenes with her father King Viserys (Paddy Considine) and young Alicent Hightower (Emily Carey) were equally enthralling. 

It was a real blow then when she left the show in episode 5, replaced by Emma D’Arcy from then on. That’s no aspersion on D’Arcy’s talent – they’re brilliant as Rhaenyra too – but Alcock was a force on screen, and I could have easily watched endless seasons more of her. 

It’s a relief then, that this is the role Gunn fixated on for his casting of Supergirl. He pulls out that it’s her edge in the show, as well as her authenticity that intrigued him, which makes me hopeful about what the DCU’s version of Supergirl might become. 

Good omens

At this stage, we still know very little about what the new film will be like. There’s no director attached yet, nor any more casting news. In fact, it’s not even clear when we’ll first see Alcock in the role – reports have suggested that we’ll meet the character first in Superman: Legacy before she helms her own movie down the line. 

However, what we do know is a loose idea of the story. The solo Supergirl film will be based on Tom King’s comic run called 'Supergirl: Woman of Tomorrow', which sees a darker twist on Kara Zor-El than fans of her other on-screen incarnations might be used to. 

Instead of a fresh-faced save-the-world type, she’s introduced at a point when her life feels meaningless. Reckoning with the trauma of her planet being destroyed as well as struggling to live life in the shadow of Superman’s fame, she’s at rock bottom. That is until Kara meets an alien girl who needs her help on the quest for revenge for the people who destroyed her home. 

In short, it’s an emotional odyssey for Supergirl, and it’s the perfect story for an actor like Alcock to show her range. As we’ve seen in House of the Dragon, she’s not a performer who shies away from darker, emotional storytelling, and if this is the edge she’ll bring to it, it’s certainly an exciting prospect.

When you pair this with Gunn too – who probably won’t be directing, but will be involved – the project gets even more tantalizing. As a filmmaker, he’s well known for his ability to toe the line between darkness and levity. Guardians of the Galaxy and Peacemaker are perfect examples of just that, and given they’re the jobs that helped land him the role at DC, they seem a fair indication of the tone of DCU: Chapter One. 

There’s some alchemy brewing over at DC then it seems, and this casting feels like the start of a major new superhero in the making. 

For more on DC, check out all the upcoming DC movies and shows as well as our breakdown of how to watch the DC movies in order.