Summary- According to some reliable sources and insider reports the news of Sadie Sink joining the cast of Avengers: Secret War has been confirmed. As of now Marvel is keeping her appearance a secret. Her character and the role in the movie are still under cover but hopefully she will play the same role as in Brand New Day. Avengers Secret War will screen on theatres from December 17, 2027.
Marvel fans, buckle up because the internet just dropped a huge announcement ahead of the release of Secret Wars. Reliable reports have confirmed that Sadie Sink is not only going to be a part of Spider-Man Brand New Day but also in Avengers’ Secret Wars.
The rumour of whether she will really be a part of the Marvel Cinematic Universe (MCU) has been going on for months in the fandom. If the reports are true, then the Stranger Things star might be stepping into one of the biggest Marvel films ever! Scroll down to read what has been officially revealed.
The Reports: Why Everyone Thinks Sadie Sink Is In Secret Wars
According to Baz Bamigboye, the editor of Deadline, Sadie will join the next Avengers film which is widely speculated to be the Secret Wars.
Confirming about the rumours, he wrote: “Spider-Man: Brand New Day is scheduled to open on July 31. There has been much speculation about the role Sink has in the Spidey film, and frankly, I do not know the answer, but I do know that she’ll join the cast of the next Avengers picture that shoots here in London later in 2026.”
Her appearance in the 2026-2027 slate aligns directly with the secret war shooting schedule.
Sadie Sink is already cast in Spider-Man: Brand New Day which is set to release in theatres on July 31, 2026. What is to be clearly noted here is the fact that her role is going to be a significant one and not just a cameo which further clears that she will remain in the MCU for further projects. Fans are already making theories about what role she might play. Let’s take a look at which Marvel character is a perfect fit for her.
The Wild Fan Theories on What Character Is Best For Sadie Sink
Since nothing is official, fans are doing what they do best – guessing! Listing down the top fan theories here.
#1. Jean Grey
Sadie’s iconic red hair makes her the ideal Jean Grey and the fans know it. Since the announcement of her being a part of the MCU, fans have been screaming this powerful mutant’s name as a perfect addition.
Jean Grey is one of the most powerful characters in the Marvel universe, possessing an unstoppable Phoenix persona in the comics.
Sadie is the one who can truly nail this character but but but, her debut in the Spidey-verse will just be so odd because Jean Grey is an X-Men character and it’d make more sense if she plays a character that is associated with Spider-Man. So we got another theory.
#2. Gwen Stacy
In Spider-Man: No Way Home, we saw Zendaya’s MJ literally couldn’t remember Peter at all. Possibilities are that Marvel may introduce a new love interest for Peter Parker who is aligned with her superhero personality, and Gwen may be a perfect replacement for MJ.
However, the set photos of Sadie didn’t reveal the iconic blonde hair of Gwen. Maybe Marvel is trying to keep it a secret.
#3. Mary J Watson
But what if, according to this wild fan theory, Peter falls for another MJ? If there are three Peters, then why can’t there be two MJs? Maybe the gate that Tom Holland’s Peter opened last time invited a different MJ, too, perhaps the one with spidey powers.
In this way Sadie won’t entirely replace Zendaya but can bring a major shift in the story.
Also Read: From Wicked For Good, 120 Bahadur and More: List of Movies Releasing in Theaters on November 21st
Signing off
Sadie Sink will definitely bring a major intensity in any Marvel character she plays. As seen in Stranger Things, he role brings an intense yet powerful side of her character.
Her rise after Stranger Things has made her one of Hollywood’s strongest young talents. She was recently nominated for a Tony Award for her role in John Proctor Is The Villain.
With no official confirmation from Sadie or Marvel, all we can do is wait and keep waiting. However, don’t forget that maybe it is not officially confirmed but major signs point towards a YES!
Written by Supriya