Milly Alcock Biography: Age, Early Life, House of the Dragon, Supergirl, Boyfriend and Career

Milly Alcock is an Australian actress who went from small television roles in Sydney to international recognition as young Princess Rhaenyra Targaryen in HBO's House of the Dragon. Born Amelia May Alcock in Sydney on April 11, 2000, she is 26 years old as of September 24, 2026. Her career expanded after Upright brought her critical attention and a Casting Guild of Australia Rising Star award, while House of the Dragon introduced her to a global audience. She later starred as Simone DeWitt in Netflix's Sirens and became the new live-action Supergirl in the DC Universe, appearing first in Superman (2025) before leading Supergirl (2026). In 2026, she also won the Critics Choice Super Award for Best Actress in a Superhero Movie for Supergirl. Her next confirmed major role is Kara Zor-El/Supergirl in Superman: Man of Tomorrow, scheduled for July 9, 2027.

Summary

• Full name: Amelia May Alcock
• Professional name: Milly Alcock
• Date of birth: April 11, 2000
• Current age: 26
• Birthplace: Sydney, New South Wales, Australia
• Nationality: Australian
• Profession: Actress
• Years active: 2013–present
• Education: Stanmore Public School; Newtown High School of the Performing Arts
• Major breakthrough: Meg Adams in Upright, followed by young Rhaenyra Targaryen in House of the Dragon
• Best-known role: Young Rhaenyra Targaryen
• Major current role: Kara Zor-El/Supergirl in the DC Universe
• Latest major released film: Supergirl (2026)
• Latest major TV role: Simone DeWitt in Netflix's Sirens (2025)
• Major 2026 award: Critics Choice Super Award for Best Actress in a Superhero Movie for Supergirl
• Current relationship: Publicly linked to London-based chef Jo Powell
• Next major confirmed project: Superman: Man of Tomorrow, releasing July 9, 2027

Early Life and Childhood

Milly Alcock was born Amelia May Alcock on April 11, 2000, in Sydney, New South Wales, Australia. She grew up in Petersham, an inner-west Sydney suburb, alongside two younger brothers. Recent profiles describe her childhood as relatively ordinary and rooted in Sydney rather than an entertainment-industry environment.

Acting interested her from a young age. One early experience that has been repeatedly mentioned in profiles of her career was playing Little Red Riding Hood in a school production at Taverners Hill Infants School. That experience helped her discover that performing was something she wanted to pursue seriously.

Her family background was not built around Hollywood or professional acting. In a 2026 Vanity Fair profile, Alcock described being raised by a single mother who worked as a nanny. She also recalled that financial difficulties encouraged her to become assertive about finding opportunities for herself. She began contacting talent agencies when she was about 13.

That early determination became an important part of her story. Rather than entering the industry through a famous family connection, she had to audition for opportunities and gradually build a résumé through Australian television.

Her childhood also appears to have been quite different from the glamorous image often associated with young actors. In interviews, she has talked about growing up with two younger brothers and being something of a tomboy. She recalled spending time around her mother's workplace and enjoying activities that were more casual than fashion-focused.

Education

Alcock attended Stanmore Public School before moving on to Newtown High School of the Performing Arts in Sydney. The specialist performing-arts school became an important part of her development because she was already pursuing acting opportunities while completing her education.

Her education took an unusual turn when she was cast in Upright. She left Newtown High School during her senior year in 2018 rather than completing the final year in the traditional way.

The decision was directly connected to the opportunity in front of her. Alcock later explained that she viewed the acting job as a more valuable opportunity than simply obtaining her school certificate. Her mother also supported the decision.

It was a major gamble, but Upright became a turning point in her career.

Beginning of Career

Milly Alcock began working professionally as a young teenager. Her early television credits included appearances in Australian productions such as Wonderland, High Life, A Place to Call Home, Fighting Season, Pine Gap, Janet King, Reckoning and The Gloaming.

These roles were generally smaller than the parts that would later make her internationally known, but they gave her experience with different kinds of television production.

In 2018, she also appeared in the Australian film The School, expanding her work beyond television. Her early credits show that she was steadily building professional experience rather than becoming famous overnight.

Her important early break came with Upright, the Australian comedy-drama created around Tim Minchin's character Lucky and teenage runaway Meg Adams.

Alcock played Meg, a teenager who meets Lucky during his journey across Australia. The character was sharp, direct and emotionally complicated, giving Alcock much more material than many of her earlier supporting roles.

The performance received strong industry recognition. In 2018, she was listed among the Casting Guild of Australia's Rising Stars, an early indication that casting professionals saw significant potential in her work.

Breakthrough

Upright

Upright became one of the most important projects of Alcock's early career.

She starred opposite Tim Minchin as Meg, and the series gave her the chance to carry a major role for an extended period. Sky's official material describes the show as a story about two lost people who form an unlikely connection while travelling across Australia. Alcock's character is a tough teenager who uses confidence and humor as a way of dealing with difficult circumstances.

Her performance earned her a nomination for the 2020 AACTA Award for Best Comedy Performer. She was later nominated for a 2023 Silver Logie for Most Outstanding Actress for the second season of Upright.

But the most significant consequence of Upright was that it helped put Alcock on the radar of the international casting team behind House of the Dragon.

House of the Dragon

In 2021, Alcock travelled to Britain to begin filming HBO's House of the Dragon, the Game of Thrones prequel.

She was cast as the younger version of Princess Rhaenyra Targaryen, one of the central characters in the story. The role required her to play Rhaenyra during a formative period before the character eventually appeared as an older woman played by Emma D'Arcy.

When House of the Dragon premiered in August 2022, Alcock's performance immediately attracted international attention. The show placed her opposite established performers including Paddy Considine, Matt Smith and Emma D'Arcy.

The circumstances surrounding her casting became part of her public story. Shortly before landing the role, she had been living in her mother's attic in Sydney and working as a dishwasher in a restaurant. She described the sudden change from that life to starring in an HBO fantasy series as extremely fast and unexpected.

She had not even been a longtime Game of Thrones fan when she auditioned. In an interview, she explained that she initially received material for an unknown HBO project and only discovered that it was connected to Game of Thrones during the audition process.

Her portrayal of Rhaenyra earned her a Critics Choice Television Award nomination for Best Supporting Actress in a Drama Series and a Critics Choice Super Award nomination for Best Actress in a Science Fiction/Fantasy Series. She also received a Saturn Award nomination for her performance.

Although Alcock appeared primarily in the first part of the series as the younger Rhaenyra, the performance became the role most closely associated with the beginning of her international fame.

Major Career

After House of the Dragon, Alcock did not simply remain attached to one fantasy franchise.

She moved into different types of work, including stage acting and television. In 2023, she made her West End debut as Abigail Williams in Arthur Miller's The Crucible at the Gielgud Theatre. This gave her an opportunity to work in live theatre after establishing herself through television and film.

Her next major screen role came with Netflix's Sirens in 2025.

Sirens

In Sirens, Alcock played Simone DeWitt, appearing opposite Julianne Moore and Meghann Fahy.

The Netflix limited series follows sisters Devon and Simone after Devon becomes concerned about Simone's close relationship with her wealthy employer. The series uses comedy, drama and social tension to explore class, family relationships and power. Netflix lists Alcock alongside Moore and Fahy as the show's principal cast.

The project was significant because it placed Alcock in a contemporary adult drama rather than another fantasy franchise. Her performance also helped demonstrate that her career could move beyond Rhaenyra Targaryen.

Entering the DC Universe

In January 2024, it was announced that Alcock would play Kara Zor-El, better known as Supergirl, in the new DC Universe.

Her first appearance came in a brief cameo at the end of Superman (2025). The role then expanded dramatically with Supergirl in 2026.

Supergirl

Supergirl became Alcock's biggest leading film role to date.

Directed by Craig Gillespie and written by Ana Nogueira, the film puts Kara Zor-El at the center of a space adventure involving revenge, justice and her relationship with her Kryptonian heritage. DC Studios officially lists Alcock as the film's lead, alongside Matthias Schoenaerts, Eve Ridley, David Krumholtz, Emily Beecham, David Corenswet and Jason Momoa.

The movie opened internationally beginning June 24, 2026, followed by a June 26 theatrical release in North America.

For Alcock, the role represented a dramatic change in scale. She went from playing a young princess in a television fantasy drama to leading a major superhero feature for DC Studios.

DC's own coverage of the film emphasized the importance of making Kara feel like a person rather than simply another superhero. Alcock and writer Ana Nogueira discussed the character's emotional history and how her version of Supergirl was intended to have a personality distinct from Superman.

Her work on the film also brought her a major award victory. On August 6, 2026, the Critics Choice Association announced Alcock as the winner of the Best Actress in a Superhero Movie category at the sixth Critics Choice Super Awards for Supergirl.

Major Movies and TV Shows

Personal Life

Family

Alcock grew up in Sydney with her mother and two younger brothers. Recent long-form profiles describe her mother as a major source of encouragement during the early years of her acting career, especially when Alcock began contacting agencies as a teenager.

She has generally kept detailed information about her family away from the spotlight. Her father's identity and private life have not been extensively documented in authoritative entertainment coverage, so details circulating on lower-quality biography websites should be treated cautiously.

Her early financial circumstances have been discussed more openly. Alcock has spoken about periods when money was tight and about working outside acting before her international breakthrough. Her experience washing dishes while living in her mother's attic became particularly notable after House of the Dragon turned her into a global name.

Relationships

As of September 2026, Alcock is publicly in a relationship with London-based chef Jo Powell.

The relationship became public through social media in 2025, and the couple later appeared together at events including the 2026 BAFTAs. People reported that the couple live together in London, while Variety's 2026 profile also described Alcock as living in London with Powell and their Persian cat, Guinness.

Alcock has generally kept the relationship private in interviews, even though the couple have appeared together publicly and shared parts of their lives on social media. There is no reliable indication from the sources reviewed that they are married. There are also no publicly confirmed children.

Earlier internet speculation linked Alcock to some of her House of the Dragon colleagues, but those alleged relationships were not reliably confirmed and should not be presented as established facts.

Philanthropy, Charity and Causes

Milly Alcock has not built a large, clearly documented personal charity profile comparable to celebrities whose philanthropic work is a major part of their public careers.

Her interviews in recent years have focused mostly on acting, creative choices, women's experiences in the entertainment industry and the pressures surrounding major franchise roles. She has spoken about wanting to work with more young women and about the importance of creating opportunities through film and television.

Because there is no sufficiently documented record of a major personal charity foundation or recurring philanthropic campaign, it would be misleading to attribute specific causes or donations to her without stronger evidence.

Awards and Nominations

The two most important wins in the current record are her early Casting Guild of Australia Rising Star recognition and her 2026 Critics Choice Super Award for Supergirl. Her earlier nominations, particularly the Critics Choice Television nomination for House of the Dragon, helped establish that her Rhaenyra performance was receiving recognition beyond the show's large fan base.

Latest Career Developments

2026 has been an important year in Alcock's career.

The biggest development was the theatrical release of Supergirl. DC lists Alcock as the lead performer in the film, playing both Kara Zor-El and her superhero identity, Supergirl. The film arrived internationally beginning June 24 and in North America on June 26.

Her performance then earned her the 2026 Critics Choice Super Award for Best Actress in a Superhero Movie.

She has also expanded her work into more unusual independent projects. Variety reported that she completed Thumb, an independent dark comedy directed by Daina Oniunas-Pusić and co-starring Sofia Vergara and Kate McKinnon. The film was listed in post-production, with no confirmed public release date at the time of the latest available production information.

Another major project is an untitled horror film directed by Japanese filmmaker Takashi Miike and featuring Charli xcx. Variety reported that Alcock spent six weeks in Japan filming the project and that the film's plot details remained under wraps.

She is also attached to Hot Mother, a thriller directed by Lucy Knox and co-starring Toni Collette. Current production information lists the project as being in development/pre-production, with no confirmed release date.

Superman: Man of Tomorrow

Alcock is confirmed to return as Supergirl in Superman: Man of Tomorrow.

The film began principal photography in 2026 and wrapped filming in August, according to director James Gunn. Variety reported that Alcock is among the returning cast following her role in Supergirl. The film is scheduled for theatrical release on July 9, 2027.

This means her DC role is not a one-film appearance. Her version of Kara Zor-El is now part of the continuing DC Universe story.

Current Projects

Net Worth

Milly Alcock's exact net worth has not been publicly verified through authoritative financial records.

One entertainment-finance site, Celebrity Net Worth, estimated her net worth at $2 million in an entry updated July 6, 2026. However, celebrity net-worth figures are generally estimates rather than audited financial statements, and different websites publish widely different numbers.

For that reason, the safest wording is that several entertainment websites estimate Millie Alcock's net worth at around $2 million, but the figure has not been independently verified by authoritative financial records.

Her income comes primarily from acting, including Australian television, HBO's House of the Dragon, Netflix's Sirens, major DC productions and theatrical work.

Career Highlights

Why 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 Stands Out

One of the clearest features of Alcock's career is the range of roles she has taken on in a relatively short period.

Meg in Upright was a grounded Australian character with a difficult life. Young Rhaenyra in House of the Dragon was a royal heir caught in a political and family conflict. Simone in Sirens moved her into a contemporary story about family, wealth and complicated relationships. Supergirl then placed her at the center of a large-scale science-fiction franchise.

Those parts are very different, but Alcock has often been drawn to characters who have strong emotions beneath the surface.

Her own comments about acting help explain that approach. In a 2026 Variety interview, she said acting gave her a safe outlet for emotions that she sometimes found difficult to express in ordinary life.

That quality was visible in House of the Dragon, where Rhaenyra's early years required a mixture of confidence, fear, sadness and frustration. In Supergirl, she had to approach another character carrying a very different kind of emotional history.

Another notable feature of her career is that she has repeatedly chosen projects outside the most obvious commercial path. After becoming known through House of the Dragon, she moved into Sirens, theatre and independent films rather than immediately attaching herself to another fantasy series.

Her 2026 interviews also show an interest in working with younger filmmakers and women in the industry, suggesting that she wants her career to include more than major franchise productions.

Legacy and Career Impact

At 26, Milly Alcock's career is still developing, so it is too early to describe a final legacy.

Her career impact so far is easier to identify.

She is one of the Australian performers of her generation to make a rapid transition from local television to major international productions. Upright established her as a young Australian performer worth watching, while House of the Dragon turned that recognition into global attention.

Her portrayal of young Rhaenyra was particularly important because the character became one of the emotional foundations of the show's opening story. Even after Emma D'Arcy took over the role of the older Rhaenyra, Alcock's performance remained central to how audiences understood the character's early development.

Her move into the DC Universe represents another major stage. With Supergirl released in 2026 and Man of Tomorrow scheduled for 2027, Alcock has become part of an ongoing superhero franchise rather than appearing in a single standalone production.

At the same time, her independent projects suggest that she is continuing to build a career outside major studio franchises.

That combination—Australian drama, fantasy television, theatre, Netflix drama, superhero cinema and independent film—has become one of the defining features of her career so far.

Frequently Asked Questions

How old is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠?

Milly Alcock is 26 years old as of September 24, 2026. She was born on April 11, 2000.

Where was 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 born?

She was born in Sydney, New South Wales, Australia, and grew up in the Sydney suburb of Petersham.

What is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 best known for?

She is best known internationally for playing young Princess Rhaenyra Targaryen in HBO's House of the Dragon and Kara Zor-El/Supergirl in the DC Universe.

Is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 married?

There is no reliable report that she is married. In 2026, she has publicly been in a relationship with London-based chef Jo Powell.

Who is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 dating?

Public reporting identifies her partner as Jo Powell, a London-based chef. The relationship became public in 2025, and the couple appeared together at the 2026 BAFTAs.

Does 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 have children?

No children have been publicly confirmed in the reliable recent profiles reviewed for this biography. She and Jo Powell have been reported as living together in London with their Persian cat.

What movies and TV shows has 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 appeared in?

Her notable credits include Upright, House of the Dragon, Sirens, Superman, Supergirl, Pine Gap, Reckoning, The Gloaming, Fighting Season and The School.

What awards has 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 won?

Her documented wins include the Casting Guild of Australia's Rising Stars recognition in 2018 and the 2026 Critics Choice Super Award for Best Actress in a Superhero Movie for Supergirl. She has also received several nominations, including for Upright and House of the Dragon.

What is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠's net worth?

There is no officially verified public figure. Celebrity Net Worth estimated her wealth at approximately $2 million in July 2026, but such celebrity-finance estimates should be treated as unverified.

What is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠 working on now?

As of September 2026, she is attached to several film projects. She has completed filming on Superman: Man of Tomorrow, which is scheduled for July 9, 2027, and is also attached to Thumb, an untitled Takashi Miike horror project with Charli xcx, and Hot Mother with Toni Collette.

What is 𝙈𝙞𝙡𝙡𝙮 𝘼𝙡𝙘𝙤𝙘𝙠's latest project?

Her latest major released project is Supergirl (2026), while her next major confirmed franchise appearance is Superman: Man of Tomorrow in 2027.

References

DC Studios — Supergirl official film page
DC Studios: Supergirl (2026)

DC Studios — Milly Alcock and Ana Nogueira on Supergirl
DC Studios interview

Critics Choice Association — 2026 Super Awards winners
Critics Choice winners

Netflix — Sirens official page
Netflix: Sirens

Casting Guild of Australia — Rising Stars
Casting Guild of Australia

AACTA — 2026 Audience Choice nominees
AACTA

Variety — Milly Alcock's 2026 Supergirl interview
Variety interview

Variety — Superman: Man of Tomorrow wraps filming
Variety report

Vanity Fair — 2026 profile of Milly Alcock
Vanity Fair profile

People — Milly Alcock and Jo Powell
People profile

Sky — Upright: Milly Alcock Q&A
Sky Atlantic interview

Critics Choice — 2023 Television Awards archive
Critics Choice 2023 archive