A wave of fan speculation has hit the Marvel community following rumors that Stranger Things star Sadie Sink is joining the cast of Spider-Man 4. While no official announcements have been made about who she will play, fans are already buzzing with theories about who she might be in the next Spider-Man installment. Some believe she may be taking on the role of Gwen Stacy or a new version of Mary Jane Watson. But one emerging theory suggests a much more unexpected and multiversal twist.