Everything we learn from the Avengers: Doomsday trailer

Marvel has finally revealed the first images of its event film. And they confirm several fan theories. We decrypt.

After months of waiting, Marvel Studios has finally lifted the veil on the first trailer forAvengers: Doomsday. The opportunity to discover Robert Downey Jr. in the skin of Doctor Doom, but also to glean many clues about the next big chapter of the MCU. Here’s what you need to remember.

Three universes will collide

The trailer comes with a never-before-seen synopsis that confirms one of the biggest fan theories. “In this new chapter of the Avengers saga, iconic heroes from different universes come together to face an unprecedented existential threat” tells us the French press release. But the American synopsis is a little more precise and evokes “heroes from three distinct universes” who will be involved in a fatal collision. Everything therefore indicates that Avengers: Doomsday will bring together Earth-616, that of the main MCU, Earth-828, where the Fantastic Fourand Earth-10005, that of the universe of X-Men from Fox. The famous “Incursions”, already mentioned in the previous films, will therefore be at the heart of the plot.

If you look closely at the screen in the background, you’ll notice three circles converging into a single point.

That could be hinting at an Incursion involving three different Earths:

– Earth-616 — the main MCU timeline.
-The Fantastic Four: First Steps Earth.
-The Fox X-Men… pic.twitter.com/Csn3j9KBm8

— Faiz Fazel (@theFaizFazel) July 20, 2026

Doctor Doom displays terrifying power

The most spectacular sequence in the trailer features the first confrontation between Thor and Doctor Doom. The God of Thunder strikes his opponent with Stormbreaker… but Doctor Doom stops the ax with two fingers, without the slightest effort. An image that says a lot about the power of the MCU’s new big bad. Stormbreaker was, however, the weapon capable of piercing Thanos, then equipped with the six Infinity Stones in Avengers: Infinity War. If Doom can stop him that easily, he might pose an even more formidable threat than the Mad Titan. One question remains: where does such power come from? Where Thanos drew his strength from the Infinity Stones, Marvel still maintains the mystery around Victor Von Doom’s abilities.

Btw
Stormbreaker cut straight through Thanos even while he had all six Infinity Stones. Doom stopped it with just two fingers. https://t.co/tdWgPMI9rr

— Echo ↬ (@vikku60879) July 20, 2026

A Doctor Doom faithful to the comics

Another detail noticed by fans: Robert Downey Jr. speaks in this trailer, with a slight Eastern European accent… A first in cinema for the character, whose Latverian origins from the comics are finally respected on screen.

Loki’s Great Return

Absent from the MCU since the end of season 2 of LokiTom Hiddleston finally makes his return.

We briefly see him in a house, a VAT card in his hand, looking out of the window. A scene which suggests that the TVA will play a central role in the multiverse war. Since becoming the “God of Stories”, Loki has protected different realities. His involvement in Doomsday therefore seemed inevitable.

Finally the reunion between Thor and Loki?

Loki’s presence obviously feeds another theory: that of his reunion with Thor.

The two brothers have not seen each other since the events ofAvengers: Infinity War. Between rivalry, reconciliation and sacrifices, their relationship remains one of the strongest in the MCU. Fans are now hoping to witness a particularly moving reunion.

Cassie Lang is back

Another detail that has gone almost unnoticed: Cassie Lang will make her return. Ant-Man’s daughter, not seen since Ant-Man and the Wasp: Quantumaniawill now appear with blonde hair, like in the Marvel comics. A scene also appears to show Scott Lang bidding him farewell before the final battle, posing a threat to Ant-Man’s fate. And its presence also raises the question of the place that the film will reserve for Young Avengersteased for ages by Marvel.

Kathryn Newton as Cassie Lang in Avengers: Doomsday 🖤 pic.twitter.com/w9k79upBe1

— bella (@johnnyslawrence) July 20, 2026

Mystique changes skin

The X-Men make a small place in the trailer. Of course, there is Cyclops who bursts the screen. And old Charles Xavier and Magneto appear briefly. But the event is above all the return of Rebecca Romijn who reprises her role as Mystique, 20 years later X-Men: The Last Stand. And in passing, she abandons the famous full blue makeup popularized by Fox. The character now wears a real costume, much closer to his appearance in the comics.

Namor and Sue Storm face to face

Finally, the trailer reveals improbable connections between characters from very different worlds. So the Fantastic Four are going to Wakanda and we find Namor in a brand new outfit. He literally opens the oceans by parting the waters, while Sue Storm uses her force fields to hold back gigantic walls of water, once again confirming the extent of her powers after the events of Fantastic Four.

Avengers: Doomsday will be released in theaters on December 16, 2026.