Jean Grey making her MCU debut in Spider-Man: Brand New Day "came out of the story," says Marvel boss Kevin Feige

At D23, Marvel boss Kevin Feige has explained why Spider-Man: Brand New Day was the right project for Sadie Sink's Jean Grey to make her MCU debut.

Sink's role was shrouded in secrecy up until release, when it was finally revealed that her mystery role was indeed the X-Men character.

"It all came out of [the] story," Feige shared at a panel celebrating 65 years of Spider-Man, attended by GamesRadar+. "[It] came out of the story that we were talking about with Amy [Pascal, producer], and with Destin [Daniel Cretton, director], and with Tom [Holland], who had a lot of story input in this film, thank goodness.

"And we were looking for a different type of mystery, and putting Peter at the forefront of being a detective, almost, for the first half of the movie, and it just sort of evolved to the point where we thought – we were looking for who could fit that bill, and it became Jean Grey," Feige continued. "I'm very glad that it did, and in large part because of Sadie Sink, because we landed on Sadie Sink and realized the connection she would have to the rest of this cast is what really locked that in."

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Sink will return as Jean Grey in the upcoming Marvel's X-Men movie. The cast was revealed onstage at D23 during the blowout studio panel: along with Sink, the cast features Kit Connor as Cyclops, Christopher Abbott as Professor X, Inde Navarette as Rogue, Maya Boyd as Storm, Samara Weaving as Emma Frost, and Adam Driver as Nathaniel Milbury (AKA Mr. Sinister).

The X-Men movie arrives this May 5, 2028. In the meantime, check out our guide to all the upcoming Marvel movies and shows, and see the major announcements from the convention with our D23 liveblog.

For more on Spidey, see our Spider-Man: Brand New Day review or how to watch the Marvel movies in order.