The ‘Spider-Man Brand New Day’ Cast Was Told to Blink Twice if Sadie Sink Is Jean Grey… and Fans Noticed

Marvel has pulled off plenty of secretive castings over the years, but few have generated quite this much sustained speculation. With the film’s release just days away, one particular mystery has managed to overshadow nearly every other storyline swirling around the upcoming Spider-Man sequel.

That mystery belongs to Sadie Sink, whose casting in ‘Spider-Man Brand New Day’ was confirmed back in March of last year without any indication of who she would actually be playing. Since then, fans have spent well over a year combing through every trailer frame, press appearance, and cryptic non-answer looking for clues.

The dominant theory by far centers on Jean Grey, the telepathic X-Men character previously played by Sophie Turner and Famke Janssen in Fox’s earlier film franchise. That theory gained traction early on given the timing of Marvel’s X-Men reboot currently in development under director Jake Schreier, along with visual hints from the trailers themselves.

Those trailers have leaned heavily into plot points involving mutated DNA and a mysterious, powerful antagonist with psychic abilities capable of taking over other people’s minds. Combined with Sink’s noticeably red hair and reported costume colors matching Jean Grey’s traditional yellow and green comic book look, the theory has only grown stronger as release day approaches.

Beyond Jean Grey, other fan theories have floated names like Spider-Girl, Firestar and Gwen Stacy as possible alternatives, though none have gathered nearly the same momentum. Marvel producer Amy Pascal offered a small hint in the film’s official press notes, describing Sink’s character as going through the same sense of isolation and alienation that every other character in the movie experiences.

Kevin Feige has also spoken about how Sink specifically came to be cast, explaining that co-producer Emily Fong suggested her for the role and that director Destin Daniel Cretton, who had worked with her before, immediately agreed she was the right fit. That explanation, while warm, notably avoided confirming any actual character name.

Sink herself has become something of a master at dodging the question entirely. During a January appearance on ‘The Tonight Show Starring Jimmy Fallon,’ she described the secrecy around her role as torture, admitting she had actually first learned about her own casting through fan theories circulating online before Marvel had even announced her involvement.

During a separate interview with a podcast host, Sink was asked to imagine walking into a store and buying jeans, specifically grey ones, a not-so-subtle attempt at getting her to slip. She laughed the question off entirely, later offering only three joking confirmations in an official Spider-Man promotional video: that she is not Spider-Man, she is not Aunt May, and she is definitely in the movie.

With ‘Spider-Man Brand New Day’ set to hit theaters on July 31, fans will not have to wait much longer to finally learn the truth. Given how tightly Marvel has controlled this particular secret across dozens of press appearances, the eventual reveal is shaping up to be one of the year’s most anticipated reveals regardless of which theory ends up being correct.

What do you think Sadie Sink’s character is really going to be? Share your predictions in the comments.