Avengers Doomsday trailer: Marvel’s biggest heroes assemble as Robert Downey Jr’s Doctor Doom threatens the multiverse

The first trailer for Avengers: Doomsday has brought together several generations of Marvel superheroes, with Doctor Doom emerging as the force threatening to tear the multiverse apart.

Avengers Doomsday trailer out

The trailer opens with a background narration by Doctor Doom, played by Robert Downey Jr, before introducing the various teams preparing to face the threat. The Fantastic Four, the X-Men and the new Avengers are all shown alongside returning members of the older Avengers, including Thor. Loki also appears in the footage.

The trailer establishes the scale of the conflict as Marvel’s heroes assemble to confront Doom and the multiverse-crossing war he is preparing to unleash.

The trailer also teases a major confrontation between Thor and Doom. The God of Thunder is seen facing the villain before the story moves towards another major reunion: Chris Evans’ return as Steve Rogers, the original Captain America. Evans’ appearance marks his first major return to the MCU since Avengers: Endgame, and his reunion with Thor is positioned as one of the trailer’s biggest emotional moments.

The X-Men are also formally drawn into the crossover, with Professor Xavier, Magneto, Mystique and Cyclops among the characters shown. Channing Tatum’s Gambit, who made his long-awaited MCU appearance in Deadpool & Wolverine, is also part of the ensemble.

The trailer further brings together the Fantastic Four and the New Avengers, the team formerly known as the Thunderbolts. Characters from across the MCU are shown sharing the screen, including heroes from the Wakandan, Shang-Chi and Fantastic Four storylines. The sheer number of characters reflects the film’s central premise: heroes from different worlds and realities must unite against a threat capable of destroying everything they know.

The footage also appears to lean into the tension that comes with bringing so many powerful groups together. Rather than presenting the heroes as an instantly united force, the trailer teases clashes and uneasy alliances between characters who have never previously shared the screen. That conflict is likely to be central to the film as the Avengers, X-Men and Fantastic Four attempt to work together against Doom.

Social media reactions to the trailer

Social media reactions to the Avengers: Doomsday trailer have focused on the sheer scale of the crossover, with fans particularly welcoming Thor’s apparent return to a more commanding role after his increasingly comedic portrayal in recent films.

One reaction said, “Thor taking center stage as a leader after being goofy is so welcomed (sic)”, while another joked about his surprise at seeing Captain America, “If Thor is so surprised after seeing cap imagine how he's gonna react after meeting Loki (sic)”.

The trailer’s Mjolnir moment also prompted laughter, with one fan writing, “Thor did second verification mode on that Mjolnir test 😂😂😂 (sic)”.

Fans also speculated about Peter Parker’s reaction to seeing Doctor Doom’s face, with one post saying, “peter parker’s gonna see doom’s face and need 40 years of multiversal therapy😭💀 (sic)”.

Others praised Thor’s apparent position as the leader of the assembled heroes, calling him “the defacto leader of the heroes here, given he's the only OG Avenger active (sic).” Doctor Doom’s imposing presence was another major talking point, with one fan writing, “Doom just not making any subtle movements and literally just standing and aurafarming is EXACTLY what I was expecting (sic)”.

The trailer’s stakes were summed up by another reaction, “You know its serious when a norse God calls for a miracle (sic)”. The sheer number of characters also left fans overwhelmed, with one writing, “ALL THESE CHARACTERS IN ONE ROOM IS SO F----NG INSANE I LOVE THE MCU (sic)”, while another reacted to the prospect of “YELENA VS MYSTIQUE OH MY GOD (sic)”.

Another fan summed up the overall response by saying, “They are pulling out absolutely everyone for this movie, and I am 100% here for it (sic)”.

More about the cast and crew

Avengers: Doomsday is directed by Anthony Russo and Joe Russo, with a screenplay by Michael Waldron and Stephen McFeely, and is based on the Avengers characters created by Stan Lee and Jack Kirby.

The film is produced by Kevin Feige, Anthony Russo and Joe Russo, and features an ensemble cast led by Robert Downey Jr., Chris Evans, Chris Hemsworth, Pedro Pascal, Paul Rudd, Anthony Mackie, Florence Pugh, Vanessa Kirby, Ebon Moss-Bachrach, Wyatt Russell, Channing Tatum, Simu Liu, Ian McKellen, Tom Hiddleston, James Marsden, Patrick Stewart, Joseph Quinn, Sebastian Stan, David Harbour, Letitia Wright, Lewis Pullman, Kelsey Grammer, Danny Ramirez, Winston Duke, Alan Cumming, Hannah John-Kamen, Rebecca Romijn, Alex Livinalli, Mabel Cadena and Tenoch Huerta Mejía.

Newton Thomas Sigel serves as cinematographer, Jeffrey Ford is the editor, and Alan Silvestri composes the music.

The film arrives in theatres on 18 December 2026.