Milly Alcock biography — the Australian actress who went from Sydney school plays to HBO royalty to the DC Universe. Discover her age, boyfriend, career, net worth, and what comes next.

The Essentials

• Full name: Amelia May Alcock, known professionally as Milly Alcock
• Born April 11, 2000, in Sydney, Australia; raised in Petersham, NSW
• Has two younger brothers
• First acting credit: playing Little Red Riding Hood in an infants school production
• Dropped out of Newtown High School of the Performing Arts in 2018 to film Upright
• Nominated for AACTA Best Comedy Performer for Upright (2019)
• Global breakthrough as young Rhaenyra Targaryen in House of the Dragon (HBO, 2022)
• Nominated — Critics’ Choice Television Award for Best Supporting Actress in a Drama Series (2023)
• West End stage debut in The Crucible at the Gielgud Theatre, London (June 2023)
• Starred as Simone DeWitt in Netflix’s Sirens alongside Julianne Moore (May 2025)
• Cameo appearance as Supergirl / Kara Zor-El in Superman (July 2025)
• Stars in Supergirl: Woman of Tomorrow (DCU film, 2026), directed by Craig Gillespie
• Currently based in London; boyfriend is chef Joseph “Jo” Powell
• Estimated net worth: $2–3 million
• Height: 5 feet 5 inches (1.65 m)

Who Is Milly Alcock?

Milly Alcock is an Australian actress whose rise from Sydney’s performing arts scene to one of the most talked-about roles in global television happened faster than most careers manage in a decade. Born Amelia May Alcock in April 2000, she grew up in the inner-western Sydney suburb of Petersham, dropped out of high school at 18 to take a television role, and has not slowed down since. She is best known for playing young Princess Rhaenyra Targaryen in HBO’s House of the Dragon, a performance that earned critical praise and a major award nomination before she turned 23. Now, as the DC Universe’s new Supergirl, she is standing at the beginning of what looks like a long run at the top of her industry.

Quick Facts: Everything to Know About Milly Alcock

Early Life & Background: A Sydney Childhood and an Early Stage

Milly Alcock grew up in Petersham, a quiet inner-western suburb of Sydney with tree-lined streets and a strong sense of community. She was the eldest child in her family, with two younger brothers, and by her own account her upbringing was relatively ordinary — far removed from anything resembling Hollywood or international stardom.

Her introduction to acting came before she could have had any clear sense of what it might become. At Taverners Hill Infants School, she played Little Red Riding Hood in a school production of Little Red Rocking Hood — a small role in a primary school play, but the kind of experience that apparently plants something lasting in certain children. It planted something in Milly.

She moved on to Stanmore Public School and then enrolled at Newtown High School of the Performing Arts, one of Sydney’s most respected selective arts schools and the training ground for a number of notable Australian performers. The school environment gave her structured exposure to drama, musical theatre, and the disciplines of live performance. By the time she was in her mid-teens, she had already begun working professionally.

Education: The School She Left Behind

Newtown High School of the Performing Arts gave Milly Alcock the foundation she needed — and she left it before finishing. In 2018, when she was cast in the Foxtel comedy-drama series Upright, she made the decision to drop out rather than delay the opportunity. She was 18 years old.

It was a significant bet on herself at an age when most of her peers were completing Year 12. The bet paid off. Upright not only launched her professionally but earned her an industry award nomination before most of her school year had finished their exams. The choice to leave — and the confidence it reflected — would prove characteristic of how she has approached her career ever since.

Career Journey: From Australian Television to Global Stardom

First Steps: Early Australian Credits (2014–2018)

Milly Alcock’s professional career began in her mid-teens with a series of small but accumulating Australian television credits. She appeared in:

• Wonderland (2013–2014, Network Ten)
• Janet King (2014)
• A Place to Call Home (sixth and final series, as Emma Carvolth)
• Fighting Season (Showcase, as Maya Nordenfelt)
• Pine Gap (Netflix, as Marissa Campbell)
• Les Norton (ABC, as Sian Galese)

She also featured in major commercial campaigns for Cadbury, Woolworths, and KFC, building the kind of screen presence and on-camera comfort that money cannot buy and drama school rarely teaches as effectively as live production experience does.

Her first feature film came in 2018 with The School, a horror film that gave her a taste of the demands of long-form character work in a genre that requires sustained emotional commitment.

Breakthrough in Australia: Upright (2019–2022)

The role that changed everything in Australia was Meg, the runaway teenager at the centre of Foxtel’s Upright, a comedy-drama in which she starred opposite comedian and musician Tim Minchin. The series follows two misfits who form an unlikely bond while transporting a piano 2,000 miles across the Australian outback.

Milly’s performance as Meg required her to carry enormous emotional weight — the character is guarded, damaged, and complicated — across both the 2019 first series and the 2022 second series. The industry responded accordingly. She received:

• A AACTA Award nomination for Best Comedy Performer (10th AACTA Awards, 2020) — one of the youngest nominees in the category’s history
• A Casting Guild of Australia Rising Star Award
• A Logie Award nomination for Most Outstanding Actress (2023)

Upright confirmed what her early credits had only suggested: that she was not simply a talented young face, but an actress capable of building and sustaining a full human being across multiple episodes of television.

Global Breakthrough: House of the Dragon (2022–2024)

In 2022, the world found out about Milly Alcock. She was cast as young Princess Rhaenyra Targaryen in HBO’s House of the Dragon, the long-awaited prequel to Game of Thrones based on George R.R. Martin’s Fire and Blood. The older version of Rhaenyra is played by Emma D’Arcy, but it was Milly’s portrayal of the character in her formative years — headstrong, politically aware, emotionally raw, and unwilling to accept the limits placed on her by a patriarchal court — that drew the loudest response from critics and audiences alike.

CNET’s Daniel van Boom wrote:

“The shining star of House of the Dragon’s opening episodes is surely Milly Alcock as Rhaenyra. She’s got an enchantingly expressive face — a simple squinting of the eyes or a pursing of the lips can betray the range of emotions that accompany king’s court politics.”

For the performance, she received a Critics’ Choice Television Award nomination for Best Supporting Actress in a Drama Series — a significant recognition for a 22-year-old appearing in her first major international production. She returned briefly for a cameo as young Rhaenyra in Season 2 in June 2024, a moment that delighted fans and demonstrated that her connection to the character had not diminished.

Stage: The Crucible, West End (2023)

In June 2023, Milly made her West End stage debut in The Crucible at the Gielgud Theatre in London, playing Abigail Williams — one of the most demanding and complex roles in the American dramatic canon. The choice to go to the stage immediately after her HBO global moment was deliberate and revealing. It signalled that she was serious about craft, not just profile.

The West End appearance also marked her transition to London as a base, where she has since remained.

Sirens (Netflix, May 2025)

Bridging her HBO career and her upcoming DCU role, Milly joined the ensemble cast of Sirens, a Netflix limited series written and executive produced by Molly Smith Metzler, adapted from her play Elemeno Pea. Milly plays Simone DeWitt, a woman who has disappeared into a wealthy beach estate lifestyle and does not want to be found by her sister Devon, played by Meghann Fahy.

The cast also includes Julianne Moore, Kevin Bacon, and Bill Camp. Critics praised the ensemble, with RogerEbert.com noting that Milly “whizzes through each scene like a fevered apparition.” The series premiered on May 22, 2025, and marked her first major role since House of the Dragon had redefined her professional standing.

The DC Universe: Superman and Supergirl (2025–2026)

In January 2024, it was announced that Milly Alcock had been cast as Kara Zor-El / Supergirl in James Gunn’s rebooted DC Universe — making her the fifth actress to play the role in live-action and the third to do so in film. She was among the first actors signed into the new DCU, suggesting Gunn himself was involved in the decision.

She made her debut appearance as the character in a cameo in Superman (July 2025), starring alongside David Corenswet. She will then lead her own standalone film, Supergirl: Woman of Tomorrow (2026), directed by Craig Gillespie (I, Tonya) and written by Ana Nogueira, co-starring Jason Momoa as Lobo. Production wrapped in May 2025.

Speaking to Vanity Fair about stepping into such a high-profile franchise for the second time, she reflected:

“It definitely made me aware that simply existing as a woman in that space is something that people comment on. I can’t really stop them. I can only be myself.”

Career Timeline & Major Milestones

Key Takeaways

• Milly Alcock built her craft across five years of Australian television before House of the Dragon introduced her to the world
• Her decision to go to the West End stage immediately after her HBO breakthrough signals a commitment to long-term artistic credibility, not just franchise fame
• She was cast as Supergirl before Supergirl: Woman of Tomorrow was even formally greenlit — a rare sign of how highly James Gunn valued her from the start
• At 26 in 2026, she has already starred in an HBO prestige series, a Netflix limited series with Oscar winners, a DC film franchise, and the West End — a range very few actors achieve at any age

Personal Life: Boyfriend, Family & Life in London

Milly Alcock is not married and has spoken openly about keeping her personal life relatively private. In June 2025, she publicly confirmed her relationship with Joseph “Jo” Powell, a London-based chef, by sharing a photo of him on Instagram wearing an “I Love My Girlfriend” shirt — what the press promptly described as a hard-launch. The couple is based in London, where Milly has lived since her West End debut in 2023.

Her family life is equally grounded. She has two younger brothers and has often spoken about the stabilising influence of her family during a period of rapid professional change. Her parents have not sought public attention alongside her rise.

Prior to Powell, she was briefly and unconfirmedly linked to director Ari Kwasner-Catsi in 2019, though the relationship was never publicly confirmed by either party.

What Nationality Is Milly Alcock?

Milly Alcock is Australian, born and raised in Sydney, New South Wales. She grew up in the suburb of Petersham in Sydney’s inner west. Despite her current London base and the international scope of her career, she has spoken warmly about her Australian roots in multiple interviews and maintains a strong sense of her national identity. She is the first Australian actress to be cast as Supergirl in the DC Universe.

Net Worth & Earnings

Milly Alcock’s estimated net worth is between $2 million and $3 million as of 2026, reflecting her HBO salary for House of the Dragon, her Netflix contract for Sirens, her DC Universe deal for the Supergirl franchise, and earlier income from Australian television and commercial work.

Her Supergirl contract, which covers at minimum two DCU appearances and potentially more as the franchise develops, is expected to be the largest single deal of her career to date. Exact figures have not been publicly disclosed.

Awards & Recognitions

• Casting Guild of Australia Rising Star Award (2019) — for Upright
• AACTA Award nomination — Best Comedy Performer (10th AACTA Awards, 2020) — for Upright; one of the youngest nominees in the category
• Critics’ Choice Television Award nomination — Best Supporting Actress in a Drama Series (2023) — for House of the Dragon
• Logie Award nomination — Most Outstanding Actress (2023) — for Upright
• Listed among Hollywood’s Rising Stars by Variety and The Hollywood Reporter

Is Milly Alcock Playing Supergirl?

Yes. Milly Alcock was officially cast as Kara Zor-El / Supergirl in the DC Universe in January 2024, making her the fifth actress to play the role in live-action. She first appeared as the character in a cameo in Superman (July 2025) alongside David Corenswet. She then leads her own standalone film, Supergirl: Woman of Tomorrow (2026), directed by Craig Gillespie and co-starring Jason Momoa as Lobo. She wrapped production on the film in May 2025. The casting was considered notable because she was signed before the film had a confirmed director — suggesting James Gunn made the decision personally rather than leaving it to the project’s director as is his usual practice.

Interesting Facts About Milly Alcock

1. Her first acting role was Little Red Riding Hood in a primary school play. The title of the production was Little Red Rocking Hood — a detail she has mentioned in interviews with a recognisable mix of fondness and amusement.
2. She dropped out of one of Australia’s most prestigious performing arts high schools to take a television role at 18 — and has never returned to formal education since.
3. She is the fifth actress to play Supergirl in live-action and only the third to do so in film, joining a lineage that includes Melissa Benoist, who publicly expressed excitement at Milly’s casting.
4. She made her West End debut — one of theatre’s most demanding stages — less than a year after House of the Dragon made her an international name. Most actors spend years trying to get there.
5. She speaks with an American accent on screen in both House of the Dragon and the DCU, a skill she began practising long before either role arrived, telling Vogue Australia in 2020 that she was already working on it just in case.
6. Her boyfriend hard-launched their relationship on Instagram by wearing a shirt that said “I Love My Girlfriend” in a photo she posted. The moment was widely covered and celebrated for its understated charm.
7. She appeared in a music video for Noel Gallagher’s High Flying Birds in January 2023, for the song “Easy Now” from the album Council Skies — a creative detour that reflects an artistic curiosity beyond acting.

Conclusion: A 26-Year-Old With Nothing Left to Prove and Everything Still to Do

Milly Alcock’s career by the age of 26 reads like a checklist someone might draw up for an actress twenty years into the business. Australian television drama, check. AACTA nomination, check. Global HBO breakout, check. Critics’ Choice nomination, check. West End debut, check. Netflix limited series with Oscar winners, check. DC Universe franchise, check. She has done all of it with a conspicuous lack of noise around her personal choices and a consistent emphasis, in every interview, on the work rather than the celebrity.

The Supergirl era is just beginning. Woman of Tomorrow in 2026 will introduce her to the widest audience of her career so far, in the role she will likely carry for the better part of a decade. But even without that, what she has already built — in Sydney, in London, in Westeros, and on a West End stage — is the kind of foundation that keeps careers going long after franchise contracts eventually expire.

She started with a school play about a girl in a red hood walking through a dark forest. What comes next is considerably brighter.