Sadie Sink Finally Breaks Her Silence on Playing Jean Grey in ‘Spider-Man: Brand New Day’ — and What Comes Next for the X-Men

For more than a year, Sadie Sink carried one of Marvel’s most closely guarded secrets.

After years of speculation from fans, the Stranger Things star officially made her Marvel Cinematic Universe debut in Spider-Man: Brand New Day as Jean Grey, one of the most powerful and complicated mutants in the history of the X-Men.

But until the movie reached theaters, Sink could barely say a word about it.

The 24-year-old actress had been offered the role after earning acclaim for performances in Stranger Things and The Whale. When she arrived on the London set of Spider-Man: Brand New Day, security surrounding the project was so intense that she had not even read the complete screenplay.

Her character was identified by a code name, and Marvel carefully avoided confirming her true identity during production or promotion.

Even the trailers kept the mystery alive.

Audiences were only shown Sink as a hooded young woman with mysterious intentions and an extraordinary ability to enter other people’s minds.

That left Sink in an unusual situation when promotional appearances began. She stood alongside co-stars Tom Holland and Zendaya, participated in interviews and attended photo calls, all while trying to discuss her role without revealing that she was actually playing Jean Grey.

For longtime Marvel fans, however, the clues were difficult to ignore.

Rumors that Sink could be playing Jean had circulated online for years, and once audiences began seeing footage of her character’s telepathic abilities, speculation intensified.

Still, Sink refused to confirm anything.

Ironically, the secret was ultimately revealed by someone else.

At the Los Angeles world premiere of Spider-Man: Brand New Day, musician Steve Lacy, who contributed a song to the movie’s soundtrack, casually referred to Jean while discussing his favorite character during the official red-carpet livestream.

He described her as the movie’s villain but suggested that there was an understandable reason behind her actions.

Instead of being upset, Sink found the accidental reveal amusing.

“Honestly, it was amazing!” she told Variety, joking that Lacy had effectively set her free after so much time spent protecting the secret.

Now that the film is in theaters, Sink can finally speak openly about becoming the third actress to portray Jean Grey in a major live-action film franchise, following Famke Janssen in the original Fox X-Men movies and Sophie Turner in the later prequel films.

The opportunity initially came as something of a surprise.

Despite the years of online speculation connecting her to Jean Grey, Sink admitted that she knew very little about the character before Marvel contacted her.

She had not even watched the previous X-Men movies.

That changed when Marvel Studios executives Kevin Feige and Louis D’Esposito arranged a meeting with her and explained who Jean Grey was, as well as how the character would fit into the new Spider-Man story.

Sink began researching Jean and quickly understood why the role carried so much weight.

She described Jean as an iconic figure in both the X-Men universe and comic-book history and said accepting the opportunity ultimately became an easy decision.

However, the version introduced in Brand New Day is intentionally different from earlier cinematic interpretations.

Rather than presenting Jean immediately as an established hero, the movie introduces her as a deeply wounded young woman whose anger and extraordinary powers have pushed her into conflict with Peter Parker.

Her relationship with her sister, Sara, becomes central to understanding her behavior.

Sink explained that giving Jean a detailed backstory was essential because some of her actions could otherwise make her appear simply villainous.

In Sink’s interpretation, Jean does not fundamentally want to hurt people.

She has been hurt herself, and that pain has shaped the only way she knows how to respond to the world.

Marvel initially told Sink that Jean would function as the villain of the movie — but also emphasized that she was not truly a conventional villain.

Sink therefore deliberately avoided portraying her with a stereotypical “bad guy” attitude.

From Jean’s perspective, her actions make sense.

The actress approached her instead as an angry, traumatized teenager trying to process loss, isolation and powers she does not fully understand.

That emotional foundation becomes especially important during the film’s later scenes involving Peter Parker.

One of Sink’s favorite moments occurs when Peter finally allows Jean into his mind, where she encounters Aunt May.

The scene forces Jean to confront feelings she has spent most of the film suppressing.

Sink said that until then, Jean deals with emotional pain through her abilities, manipulation and anger. But in that moment, those defenses finally collapse.

For all her strength, Jean is ultimately terrified and alone.

Her resentment toward Peter partly comes from believing that he still possesses something she has lost: meaningful human connection.

The movie also uses MJ as part of Jean’s psychological manipulation of Peter, forcing him to remember the relationships and life that he can no longer fully have.

But eventually Jean recognizes that Peter understands loneliness and grief more than she assumed.

Instead of allowing loss to destroy him completely, he attempts to use what he has learned from it to help her.

For Sink, that exchange reveals the emotional core of Jean Grey.

It was also especially meaningful because the sequence was reportedly filmed on her final day working on the movie.

Playing a character with powerful telepathic abilities also created unusual technical challenges.

For scenes in which Jean controls other characters, Sink and Holland rehearsed extensively.

The production then filmed Sink performing all of Jean’s dialogue for scenes in which she would later speak through another person.

Those recordings were distributed to the actors as references so that they could reproduce elements of Sink’s rhythm, behavior and physicality.

Zendaya’s interpretation particularly impressed her.

Sink said she had not seen Zendaya’s version while filming and only discovered how she had incorporated Jean’s mannerisms when she later watched the finished movie.

The role also demanded considerable physical effort.

Sink recalled spending long periods strapped into a chair while shooting scenes involving Jean being experimented on. Although those moments pass quickly on screen, they required repeated takes and extensive coverage.

The physical strain left her neck sore, but Sink said she actually enjoys demanding physical work because it helps connect her body to a character’s emotional state.

Despite the enormous scale of Spider-Man: Brand New Day, Sink worked on the movie for only about 20 shooting days.

Much of her involvement happened during preproduction and rehearsals, particularly as the filmmakers established how Jean’s powers would physically affect other characters.

Joining the Marvel universe could have been intimidating, but Sink had one major advantage: director Destin Daniel Cretton was already familiar to her.

She had previously worked with him on The Glass Castle when she was younger.

Sink said having someone she trusted behind the camera made entering a franchise as enormous as Spider-Man and Marvel significantly easier.

She compared the experience to joining Stranger Things during its second season, when she entered an already established cast as the new character Max Mayfield — only on an even larger scale.

Cretton’s vision for Jean was also clear from their earliest conversations.

Rather than focusing on making her seem threatening, he wanted audiences to see a young woman in pain.

That approach gave Sink a recognizable emotional foundation: an angry, hurt teenager searching for control and identity.

Now that Brand New Day has revealed Jean Grey to the world, attention is already turning toward her future.

Sink has confirmed that Jean will return in Marvel’s upcoming X-Men movie.

She cannot reveal how many Marvel projects she has signed on for, and even questions about exactly where Jean is heading at the end of Spider-Man remain unanswered.

But Sink is enthusiastic about what comes next.

The more she has researched the X-Men, the more she has become interested in what separates them from conventional superheroes.

To Sink, mutants are compelling because their powers do not automatically make their lives better.

Often, those abilities make their lives considerably harder.

The X-Men are flawed people who may make serious mistakes before learning what their powers mean and how they want to use them.

That makes Jean’s troubled introduction in Brand New Day especially important.

Instead of beginning as a polished superhero, audiences first meet her during one of the darkest and most emotionally unstable periods of her life.

Her eventual journey toward becoming part of the X-Men can therefore be built around growth rather than simply power.

Sink has not yet met some of the actors rumored to be joining the new ensemble, including Kit Connor as Scott Summers, better known as Cyclops, and Samara Weaving as Emma Frost.

But she is already excited by the possibility of becoming part of a larger mutant cast.

For an actress who once admitted she knew almost nothing about Jean Grey, that enthusiasm represents a dramatic transformation.

A role that began with a secret Marvel meeting, a mysterious code name and months of carefully avoiding spoilers has now become one of the most important new chapters of her career.

And Spider-Man: Brand New Day may only be the beginning.

Jean Grey has officially entered the MCU.

Now Sadie Sink finally gets to talk about her — and prepare audiences for wherever Marvel takes one of the X-Men’s most powerful mutants next.