What's Inside?
- Insider hints strongly suggest Sadie Sink could portray Gwen Stacy, marking a major addition to Spider-Man: Brand New Day.
- Gwen Stacy’s MCU debut could follow classic storyline or introduce Spider-Gwen, offering fresh possibilities for Tom Holland’s Peter Parker.
- With Stranger Things ending, Sadie Sink’s MCU role could open long-term opportunities in future Spider-Man films and Marvel crossovers.
Marvel fans may finally have a clue about who Sadie Sink will portray in Spider-Man: Brand New Day, the highly anticipated fourth solo film starring Tom Holland as Peter Parker. While Marvel Studios has kept her role under wraps since announcing her casting, a recent report has sparked major buzz, and if true, it could mark a huge moment for the MCU’s Spider-Man storyline.
Insider Suggests Gwen Stacy is on Her Way to the MCU

According to insider Kristian Harloff, it’s a “pretty good guarantee” that Sadie Sink has been cast as none other than Gwen Stacy, one of Spider-Man’s most iconic characters. While this is not yet confirmed, the rumor has quickly ignited speculation across the fandom. Gwen Stacy has appeared in live-action before, portrayed by Bryce Dallas Howard in Sam Raimi’s Spider-Man 3 and by Emma Stone in The Amazing Spider-Man films.
BREAKING‼️
Sadie Sink secret character in Spider-Man: Brand New Day has reported to be none other than Gwen Stacy! #SpiderManBrandNewDay
Via @RealScreenGeek pic.twitter.com/8eJedkArgk
— Culture Base 🍿 (@Culture3ase) August 8, 2025
In recent years, the character has gained renewed popularity thanks to the animated Spider-Verse films, where “Spider-Gwen”, an alternate-universe version of Gwen Stacy who becomes a superhero, has become a fan favorite. If the MCU decides to explore this direction, Sadie Sink could potentially bring a fresh and dynamic take on Gwen to live-action.
A Perfect Career Move as Stranger Things Wraps Up

With Stranger Things nearing its conclusion, Sink has more freedom to take on blockbuster projects. Joining the MCU not only cements her place in another pop culture juggernaut but also opens the door for recurring appearances in future Spider-Man films and possible crossovers.
If Gwen Stacy is indeed part of Spider-Man: Brand New Day, her arrival could signal a shift in Peter Parker’s journey following the dramatic events of No Way Home. Whether Marvel sticks to the traditional Gwen storyline or introduces a superhero version, the casting could be one of the film’s biggest talking points.
Production on Spider-Man: Brand New Day is already underway, with the movie set to hit theaters on July 31, 2026. Until Marvel makes an official announcement, fans will be left to speculate — but if Harloff’s scoop proves accurate, Sadie Sink’s MCU debut might be even bigger than expected.