One of the stars behind Avengers: Doomsday shared a new photo online that has fans convinced it was taken in the X-Mansion from the Fox X-Men universe. After bringing their interconnected comic book universe to a close with Disney's purchase of 20th Century Fox, several classic Fox X-Men characters will finally return to the big screen as a part of Marvel Studios' next Avengers team-up.
Coming with the team of legacy mutant characters is assumed to be their base of operations, the iconic X-Mansion in Westchester, New York. Fans seem to think they may have gotten a look inside the legendary comic book locale in a new image shared by Avengers: Doomsday star Simu Liu, as the 2026 film winds down production.
Liu, who will reprise his role as Shang-Chi in the upcoming Avengers film, shared the conspicuous photo on his personal Instagram Stories (via Marvel Avengers on X). It shows him and several others sitting down for a meal in a wood-paneled room that looks strikingly similar to the X-Mansion.
While it is unclear whether this is on the Avengers: Doomsday set (why would Liu post a public photo of the hyper-secretive movie production if it was?), it is hard not to argue that the baroque wood panelling does not closely resemble the architecture of the Fox X-Men home base.
Also, several bits of filming equipment, including a light and a camera, can be seen in the image, lending credence to the theory that this could be the X-Mansion as seen in Doomsday.
Since even before Doomsday filming began, there were rumors that the upcoming MCU team-up would be headed to the X-Mansion in some capacity. Set photos released in June 2025 seemingly revealed a peek behind the curtain at an epic battle at the comic book locale, with the Avengers rumored to clash with Fox's X-Men characters.
Avengers: Doomsday, releasing in theaters on December 18, 2026, will see the lines between the MCU and Fox X-Men universes blur like never before, as the Avengers cross paths with other heroes from across the Marvel canon. Classic mutant actors/characters confirmed to appear include Patrick Stewart as Professor X, James Marsden as Cyclops, and Sir Ian McKellen as Magneto.
How Will the X-Men Factor Into Avengers: Doomsday?
For as long as there have been comic book movies, fans have been ravenous to see the Avengers cross paths with the X-Men on the silver screen.
After 2024's Deadpool & Wolverine broke the walls between the MCU and Fox's former X-Men universe, the super-powered team-up the Marvel faithful have been waiting for will finally shine in next year's Avengers: Doomsday.
How these marvellous mutant characters will factor into Avengers 5 remains a massive question mark for fans, though.
According to some reporting on the movie, despite Robert Downey Jr.'s Doctor Doom seemingly being a common villain between the two teams, Doomsday will pit the Avengers and X-Men against one another, with the winner getting to see their reality survive.
This feels like the most likely scenario, with the X-Men battling it out with the Avengers before realizing what is at stake and banding together with Earth's Mightiest Heroes to take on Doom in either Doomsday's third act or its 2027 sequel, Avengers: Secret Wars.
Of course, all this will lead to the MCU introducing its own version of the X-Men and X-Mansion post-Secret Wars after giving the Fox X-Men Universe its final hurrah to close the Multiverse Saga.
