Big comic-based movie trailers that will be discussed at San Diego Comic-Con (SDCC) are usually released during the weekend of the big show. This year, Marvel has flipped that script by releasing the first full-length trailer for Avengers: Doomsday a week before the con, and fans have plenty to discuss.

The trailer is packed with characters as the Marvel Cinematic Universe ventures into the Multiverse. It starts with an ominous voiceover from Doctor Doom (Robert Downey, Jr.) while Charles Xavier (Patrick Stewart) witnesses an explosive phenomena outside his window. Avengers tower is shown where Thor (Chris Hemsworth) and the Fantastic Four meet with the new Captain America (Anthony Mackie), Ant-Man (Paul Rudd), and the New Avengers (aka, Thunderbolts*).

It cuts to a tense meeting between the new Black Panther (Letitia Wright) and the Wakandans with Namor (Tenoch Huerta) and the Talokanil. As Thor narrates about the threat they are facing, the trailer delivers brief shots of the many characters in the movie. We see Thor landing near Doctor Doom, Cyclops (James Marsden) using his powers, Shang-Chi (Simu Liu) fighting Gambit (Channing Tatum), and the return of Loki (Tom Hiddleston). The Wakandans meet the Fantastic Four, Mystique (Rebecca Romijn) goes up against Yelena Belova (Florence Pugh), and more exciting character teases.

A preview of a fight between Thor and Doom leads into the trailer’s biggest moment. As Thor’s voiceover continues he claims that they will need a miracle, and one appears in the form of Steve Rogers (Chris Evans).

Avengers: Doomsday is the first massive gathering of MCU characters since 2019’s Avengers: Endgame. Marvel had initially planned to pit the Avengers against Kang, but that changed after actor Jonathan Majors was fired from the role. Instead of recasting Kang, who had made appearances in the Loki series on Disney+ and in Ant-Man and the Wasp: Quantumania, Marvel pivoted to a battle with Victor von Doom.

During SDCC in 2024, Marvel revealed that beloved Iron Man actor Downey would take on the role of Doctor Doom. Months later in March 2025, Marvel announced the huge cast that would appear in the movie that included current MCU star joined by actors who portrayed Marvel characters going back to 20th Century Fox’s X-Men film that was released in 2000.

In addition to the cast mentioned above, Avengers: Doomsday stars Pedro Pascal, Vanessa Kirby, Ebon Moss-Bachrach, and Joseph Quinn as the Fantastic Four; Sebastian Stan, David Harbour, Wyatt Russell, Hannah John-Kamen, and Lewis Pullman as the New Avengers; Winston Duke as M’Baku and Danny Ramirez as the new Falcon; and X-Men franchise stars Ian McKellen, Kelsey Grammer, and Alan Cumming.

The movie will be discussed at San Diego Comic-Con during the “Marvel Studios Hall H Presentation” on Saturday, July 25 at 5:30 PM in Hall H. The studio will provide exclusive looks at Doomsday and their other upcoming projects.

Avengers: Doomsday will be in theaters on December 18, 2026.