After months of speculation, Sink was officially revealed as Jean Grey, one of Marvel's most iconic and powerful mutants. Now Sink gets the opportunity to introduce a brand-new version of Jean Grey as Marvel Studios begins building its own era of mutants. While Feige confirmed Jean Grey has an important future, he stopped short of revealing exactly where she'll show up next. It doesn't appear that either Sink's Jean Grey or Tom Holland's Spider-Man will appear in Avengers: Doomsday. Now that the mystery surrounding Sadie Sink's role has finally been revealed, the bigger question is where Jean Grey fits into Marvel's mutant future.