Spider-Man: Brand New Day is set to hit theaters in 2026, bringing plenty of exciting updates to its cast — the biggest being the addition of the talented actress Sadie Sink.

Best known for her breakout role as Max in Stranger Things, the Netflix hit, Sadie is now ready to join the Marvel Cinematic Universe. However, her casting remains both the film’s most thrilling reveal and its biggest mystery. So far, neither Marvel nor Sony has confirmed who she’ll be playing.

Spider-Man: Brand New Day leaks first look at Sadie Sink!

Filming for Spider-Man 4 began in August and has taken place in several public locations, which naturally led to many on-set photos surfacing online. This time, thanks to photographer UnBoxPHD, fans finally got their first glimpse of Sadie Sink on set — check it out below.

Photographers captured the actress covered up, hiding most of her costume. Fans could glimpse only her pants and boots, which sparked even more speculation about her character’s identity.

Who is Sadie Sink playing in Spider-Man 4?

According to a rumor shared by Dborn, a Reddit insider known for accurate Marvel leaks, Sadie Sink could be portraying Shathra, a villain from another dimension. In the comics, Shathra is a shape-shifting being who can assume multiple forms and poses a major threat to Spider-Man.

However, this choice would contrast with Marvel’s statement that Spider-Man 4 will have a more grounded, street-level tone.

Even so, everything points to a major twist surrounding Sadie Sink’s mysterious role. That may be why both Marvel and Sony are keeping her character’s identity a secret — saving the reveal for a surprising moment in the film.

It’s worth noting that the new Spider-Man movie will hit theaters on July 31, 2026. So, what do you think? Share your thoughts in the comments — and stay tuned for all the latest updates!