Spider-Man 4 Adds Stranger Things Star Sadie Sink

The first new cast member has joined Sony’s upcoming Spider-Man 4 and it’s a very intriguing one. Deadline reports that Sadie Sink, best known for her work on Stranger Things, has joined the cast of the 2026 film but there’s a big question as to who she’s playing.

The trade reports that it’s an important role, which makes sense. Sink is well beyond cameo status these days. She was also one of the actresses most closely linked with playing popular X-Men character Jean Grey, which would be incredible, but the trade says she could be someone else.

A comic book fan might make the assumption that casting a red-head in Spider-Man movie means you’re casting Mary Jane Watson. But considering we already have one in Zendaya, it’s clear that’s off the table (unless there’s the not-insignificant possibility that Sink is playing a “variant” of the character that more aligns with MJ’s classic comics appearance). Speaking of the multiverse, there’s an equal potential chance that Sink could be a version Gwen Stacy–either in the traditional role of another love interest for Peter, or in her own variant form as Spider-Gwen.

Stacy makes more sense from a plot standpoint just because, following the events of No Way Home, we can assume Peter Parker (Tom Holland) will need new friends. And since Zendaya basically played the Marvel Cinematic Universe equivalent of Mary Jane Watson, next on the Spidey-list is Stacy, who was portrayed by Emma Stone in the Andrew Garfield films.

Introducing Jean Grey here could be fun too though. It would certainly mess with the typical X-Men dynamic of Logan and Scott Summers fighting over her. I, for one, welcome a fight between Wolverine, Cyclops, and Spider-Man. Slowly introducing X-Men in other films feels very MCU too. But, again, is that getting too far away from Spider-Man’s story? Without a doubt. Especially when there is another redheaded mutant with closer ties to Peter’s own story that would still allow Marvel and Sony the cake-and-eat-it of slowly seeding mutantkind into the movieverse once more: Angelica Jones, a.k.a. Firestar, the mutant flame-manipulator originally created for the 1981 animated series Spider-Man and His Amazing Friends, who eventually made her own way into the comics as a regular Avengers and eventual X-Men character.

The fact is though, while Spider-Man 4 is expected to start filming later his year aiming at an (increasingly unlikely) summer 2026 release date, we don’t know what it’s going to be about. Will it be a street-level story like Homecoming? Or will it embrace the multiverse again like No Way Home? Maybe we’ll find out a bit more next month when Sony Pictures returns to CinemaCon in Las Vegas.

For now though, what do you think about Sadie Sink in the Spider-Man universe? Let us know below.

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