Sadie Sink reveals who on 'Stranger Things' set knew about her 'Spider-Man' role

Sadie Sink has revealed, to Variety, that only a small group of people were aware of her casting as Jean Grey in Spider-Man: Brand New Day before the role was made public.

The 24-year-old actress, best known for playing Max Mayfield in Stranger Things, said she kept the Marvel casting confidential after being selected in March 2025.

She confirmed that only her family and a few trusted industry figures were told, including Stranger Things creators Matt and Ross Duffer.

“I mean, it was definitely more than three, if I'm being honest. You have people that you can trust within the industry to talk about it. So, my family knew and everything, and then I slowly … like the Duffers were some of the first few people I told. Because I was filming with them, and they're obviously huge influences in my career and life, and have watched me grow up, so I wanted them to know that that's what I would be doing next. And they were so excited.”

Sink said the Duffer brothers were supportive of her decision and immediately encouraged her to take on the role.

“Well, they were just like, 'That's the best character. You have to do it!' and like, 'That's perfect. You're going to be amazing,' and blah blah blah. They thought it was the right fit for me, and I trust their opinion because they love comics and stuff like that, and are very well versed with these characters, so it was good to have their input.”

Despite her long association with Stranger Things, Sink said she did not inform the wider cast about her Marvel role.

“I didn't really tell anybody else [from Stranger Things]. That was kind of it.”

She also admitted she was unfamiliar with Jean Grey and had not seen the X-Men films when she was cast in Spider-Man: Brand New Day.