Downey suited up as Mister Fantastic and Pascal threw on Doctor Doom’s cape in a Halloween costume swap, seven weeks before Avengers: Doomsday hits theaters on Dec. 18.
Robert Downey Jr. and Pedro Pascal are about to fight each other in the biggest Marvel movie of the year. So for Halloween, they traded places.
Downey posted a short Instagram video over Halloween weekend showing himself in Mister Fantastic’s blue Fantastic Four suit, big “4” on the chest and all, with a white belt. Pascal, who actually plays Reed Richards, wore Doctor Doom’s cape with a silver Doom mask pushed up on his head.
The caption, as quoted by Fiction Horizon, Deccan Chronicle and India TV: “Victor. Richard. Costume swap!”
Yes, it says “Richard,” not “Reed.” Whether that’s a typo or a Downey joke, nobody has said.
What did Pedro Pascal wear under the Doctor Doom costume?
A gray sweatshirt reading “MIT,” according to Comic Basics and Fiction Horizon. That small detail got fans going, since Reed Richards is the brainy one in the Fantastic Four and Doom is, well, the guy with the mask.
In the clip, Pascal laughs with his hands over his face before copying Doom’s crossed-arm pose. Downey just stands there in blue spandex like it’s a normal Saturday.
Nobody else shows up in the video, per Fiction Horizon. Comic Basics reported the reel picked up hundreds of thousands of views within hours.
Who does Robert Downey Jr. play in Avengers: Doomsday?
Victor von Doom. Downey shocked the room at San Diego Comic-Con in July 2024 when he pulled off a mask on stage and said “New mask, same task.”
It’s a big swing for the actor who launched the whole Marvel Cinematic Universe as Tony Stark back in 2008. Stark died in Avengers: Endgame in 2019, so Downey coming back as a villain was the last thing most fans expected.
Pascal played Reed Richards in The Fantastic Four: First Steps, which opened in July 2025. He’s set to play him again in Doomsday and in Avengers: Secret Wars, per Fiction Horizon.
When does Avengers: Doomsday come out?
Avengers: Doomsday opens in U.S. theaters on Friday, Dec. 18, 2026. Early previews start Thursday, Dec. 17.
Joe and Anthony Russo are directing. They’re the pair behind Avengers: Infinity War and Avengers: Endgame.
The cast list is stacked. Chris Evans, Chris Hemsworth, Anthony Mackie, Paul Rudd, Florence Pugh and Tom Hiddleston are all in it. So are the Fantastic Four’s Vanessa Kirby, Joseph Quinn and Ebon Moss-Bachrach, plus X-Men veterans Ian McKellen, Patrick Stewart and Channing Tatum.
Stewart’s return carries extra weight now. PNP reported his death on Oct. 29, so fans will be watching his scenes closely.
Doomsday also opens the same day as Dune: Part Three. Comic Basics and Fiction Horizon both point to tracking that has advance ticket sales above $100 million worldwide, but that’s an estimate, not an official number.
Are Robert Downey Jr. and Pedro Pascal friends in real life?
Seems like it. Downey has been one of Pascal’s loudest fans.
In 2025, Downey said Pascal’s “slow trajectory to becoming a household name who is on a wildly hot streak” kind of “reaffirms my faith in our industry.”
Downey also hosted what he called “homework days” at his house during Doomsday filming, with castmates including Pascal coming over to prep.
So the costume swap wasn’t exactly out of nowhere. It’s two guys who like each other, goofing off before they spend a whole movie trying to wreck each other’s day.
What else did Marvel do for Avengers: Doomsday on Halloween?
Downey also shared a cartoon of Doom out trick-or-treating with a group of tiny witches. A Fantastic Four member hands him a treat that is, let’s just say, not what Doom had in mind.
Over in South Korea, Marvel lit up the sky over Seoul’s Han River with a drone show for the movie this past week. PNP covered that one on Oct. 31.
And movie theaters are already rolling out Doom popcorn buckets. Doom sells popcorn now. Rough week for the Fantastic Four.
Fan comments under the post ran from “What universe are we in?” to “This is the best thing ever,” per Fiction Horizon and Deccan Chronicle.
Seven weeks to go. If the stars are this loose about it, the press tour is gonna be a lot of fun.
Article compiled and written by Kambrea Pratt (editor-in-chief), Derek Gibbs (beat editor) and the Pirates & Princesses newsroom. Pirates & Princesses is part of WebReef Media.
Pirates and Princesses is your destination for Disney news, theme park updates, and the pop culture you love. From Disney cruises and travel tips to Disney fashion, food, collectibles, and movie news, PNP covers it all. Visit us at piratesandprincesses.net for daily coverage. Follow PNP on Facebook and Instagram, and listen to the Pirates & Princesses podcast on Apple Podcasts and YouTube.
Hat Tips:
Fiction Horizon (Nov. 1, 2026), the caption, costume details and fan comments
Comic Basics (Nov. 1, 2026), the MIT sweatshirt, view count and Doom cartoon
Deccan Chronicle (Nov. 1, 2026), caption and cast list
Deadline (Oct. 31, 2026), first report of the costume swap
ScreenGeek (July 14, 2025), Downey’s quote on Pascal
Marvel Entertainment (Aug. 14, 2026), the Avengers: Doomsday “Special Look” video
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