'Avengers: Doomsday' official trailer offers sneak peek at Robert Downey Jr.'s take on Doctor Doom

"Something's coming. Something we may not be able to deter before this day is done." Marvel Studios debuts the official trailer for "Avengers: Doomsday," also revealing the first look at Robert Downey Jr. as villain Doctor Doom.

In the trailer, Chris Hemsworth as Thor declares, "I've fought with many warriors in my time, who were far stronger than all of us put together. And, they died. They died facing enemies and threats that scared me far less than this one."

The "Avengers: Doomsday" trailer unveils beloved superheroes from "three distinct universes" working together on a "deadly collision course" to take on an "existential threat unlike anything they've ever encountered."

X-Men characters including Professor X, Cyclops, Nightcrawler and Magneto will return to the big screen. The Fantastic Four members Mister Fantastic, Invisible Woman, Human Torch and The Thing will be included on the mission. Plus, the original Avengers team led by Sam Wilson's Captain America as well as the New Avengers with Yelena Belova and Bucky Barnes.

The newest Marvel movie also stars Chris Evans, 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, Kathryn Newton, Danny Ramirez, Winston Duke, Alan Cumming, Hannah John-Kamen, Rebecca Romijn, Mabel Cadena, with Tenoch Huerta Mejia.

Before "Doomsday" arrives, catch up with "The Avengers" movies and shows streaming now on Disney+.

"Avengers: Doomsday" releases exclusively in theaters Dec. 18. Tickets are on sale now for Infinity Vision certified screens.

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