You might assume a five-hour video of chairs labeled with names would be devoid of Marvel Cinematic Universe Easter eggs, but dedicated fans are convinced one is hidden in the shadows.

To recap, Marvel recently unveiled the cast of Avengers: Doomsday through a video that gradually presented chairs bearing the names of MCU actors. The video confirmed 26 additional actors joining Robert Downey Jr.’s Doctor Doom in the epic superhero ensemble. This reveal stretched close to five and a half hours.

While most have moved on to debating what the casting means for Avengers: Doomsday itself, a few persistent viewers have scrutinized the chairs and their shadows frame by frame. Now, they believe they've uncovered… something.

Redditor True_Confusion_297 aptly remarked, “I feel like a conspiracy theorist circling things in red,” highlighting a shadow cast by one chair that seems to form an "X" atop an "A." The interpretation? A potential hint at Avengers vs. X-Men.

I feel like a conspiracy theorist circling things in red
byu/True_Confusion_295 inmarvelstudios

Marvel surprised many by confirming the return of several stars from Fox’s X-Men films. Veterans including Kelsey Grammer, Patrick Stewart, Ian McKellen, Alan Cumming, Rebecca Romijn, and James Marsden are now set to appear in Avengers: Doomsday. Grammer, known for his role as Beast in the Fox X-Men series, recently made his MCU debut in a post-credits scene in The Marvels. Stewart, who played Charles Xavier/Professor X, previously appeared in the MCU as part of the Illuminati in Doctor Strange in the Multiverse of Madness. McKellen (Magneto), Cumming (Nightcrawler), Romijn (Mystique), and Marsden (Cyclops) have yet to make their MCU debuts. Even Channing Tatum is returning as Gambit following his appearance in Deadpool & Wolverine. This naturally raises the question: could Avengers: Doomsday secretly be an Avengers vs. X-Men movie?

When the film finally premieres, fans might look back on this moment, pointing to a chair's shadow as the first tease of the long-awaited superhero showdown. Or maybe not.

The shadow letter theory isn’t the only speculation emerging from Marvel's announcement video. At the end, Robert Downey Jr. gives a slightly unsettling 'shhh' gesture to the camera, placing a finger to his lips. Why? Is it a ‘don’t tell anyone’ warning as production nears? A teaser for Avengers: Secret Wars? A nod to more casting news on the horizon?

Or could it be a reference to Agatha in WandaVision—and, by extension, a surprise appearance of Scarlet Witch, despite actress Elizabeth Olsen suggesting she won't return?

Doom x Agatha.#AvengersDoomsday pic.twitter.com/3LX38W5Kc0

— Cosmic Marvel (@cosmic_marvel) March 26, 2025

Earlier this month, co-directors the Russo brothers described Avengers 5 and 6 as a “new beginning,” establishing the foundation for Phase 7 of the MCU.

“Here’s what I can share: we love villains who see themselves as the heroes of their own stories,” Joe Russo explained. “That adds depth and makes them compelling. With an actor like Robert Downey Jr., it's essential to craft a multidimensional, well-developed character for the audience. That’s a major focus for us.”

Avengers: Doomsday is scheduled to hit theaters on May 1, 2026, followed by Secret Wars around a year later in May 2027. Before then, Thunderbolts* releases in May 2025, the Ironheart series arrives in June, and Phase 6 begins with The Fantastic Four: First Steps in July.

In October, Marvel Studios added three untitled films to its 2028 lineup: February 18, 2028; May 5, 2028; and November 10, 2028. Many now speculate that one of these could be an X-Men film.