'Avengers: Doomsday' trailer secrets revealed: What we know so far

Robert Downey Jr. is back in the Marvel Cinematic Universe, but not as Tony Stark.

The 60-year-old Hollywood legend will take on the role of the archvillain Doctor Doom in Avengers: Doomsday, and fans are buzzing with questions about what his return actually means.

Since Comic-Con 2024, Marvel has been drip-feeding little more than teases, focusing on the jaw-dropping cast rather than the plot. 

The upcoming blockbuster reportedly brings together the Fantastic Four, the old Avengers, the new Avengers, and even the X-Men from the 20th Century Fox era. 

So far, some actors have admitted they’re unsure who they’re sharing scenes with or what’s going on, leaving audiences equally mystified.

Notably, an 85-second trailer is expected to debut ahead of Avatar: Fire and Ash, which premieres on December 19, giving fans their first real glimpse of the action almost exactly a year before the film hits cinemas on December 18, 2026.

While Doom made a silent mid-credits cameo in Fantastic Four: First Steps, RDJ’s take on the villain and the multiversal chaos at play remain under wraps. 

One thing’s clear, that every hero in the MCU is going to have to team up to stop him from claiming Franklin Richards’ cosmic power. 

Finally, Marvel fans might get a peek at the stakes in what promises to be the most epic showdown yet.

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