When it was announced that Sadie Sink had joined the cast of Spider-Man: Brand New Day, there was already a bit of online chatter relating to the Stranger Things alum potentially joining the MCU.
A rumor had been doing the rounds that Sink was being eyed to play Jean Grey in Marvel Studios' X-Men reboot, but the initial trade report appeared to hint that she had more likely been cast as Mary Jane Watson. Since then, a lot of follow-up rumors have done the rounds, with multiple sources naming various different characters such as Jackpot, Gwen Stacy, Menace, and even Mayday Parker.
So far, the only "official" (ie, trade-reported) details about Sink's character that have been disclosed are that she is playing a "sharp and free-spirited" woman who has a "mysterious past."
We're still not sure who Sink is playing, but we may have a better idea of why there is so much secrecy surrounding her role.
Possible spoilers ahead.
We have heard that there is some kind of big twist relating to Sink's character that the studio is doing its best to keep under wraps. We don't have much more to go on for now, but this could explain why there are so many conflicting reports out there (it wouldn't be the first time a studio "leaked" false character details to throw the scoopers off, after all). It may also support a recent rumor that Sink's character will be an ally to Peter Parker (Tom Holland), but not necessarily Spider-Man.
Will Sink be introduced as one character only to be unveiled as someone else as the movie progresses, perhaps? That's one possibility, but we're heading into speculation territory here.
Hopefully, we'll see Sink on the London set at some point over the next week or so, and finally learn who she's actually playing.
Spider-Man: Brand New Day will also star Jon Bernthal as Frank Castle, Mark Ruffalo as Bruce Banner/The Hulk, Michael Mando as Mac Gargan/The Scorpion, and Liza Colón-Zayas in an undisclosed role. Zendaya and Jacob Batalon will reprise their respective roles as MJ and Ned Leeds, but are not expected to feature prominently.
"It's day one — my fourth-ever day one on Spider-Man," Holland said in the recently-released BTS video. "You know, it's funny. Putting the suit on, it feels different this time, somehow. It's also the first time we've ever had fans on set for day one, so it's really exciting to share this with them. We've got some familiar faces on set. You know, Im just going to do my best, hopefully get it right. No pressure."
Spider-Man 4 was recently pushed back a week from July 24, 2026 to July 31, 2026.