Anthony Mackie returns as Captain America in new trailer for Marvel's 'What If...?'

Anthony Mackie, Oscar Isaac, Simu Liu, and more Marvel stars return to voice their characters in the final season of "What If...?" streaming December 22 on Disney+.

LOS ANGELES -- The Marvel series "What If...?" is back for its final season, and the new trailer highlights the unique encounters these heroes will face.

The animated series explores the possibilities within the Marvel Cinematic Universe and this season takes things to the next level with new characters, fresh genres and bigger spectacles.

Join the Watcher, voiced by Jeffrey Wright, as he guides you through episodes set in cowboy-themed worlds, Avengers in Power Ranger-like mechs and one where Storm wields Thor's hammer.

Anthony Mackie, Oscar Isaac, Simu Liu, and more Marvel stars return to voice their characters in the final season of "What If...?"none

Anthony Mackie, Oscar Isaac, Simu Liu, and more Marvel stars return to voice their characters in the final season of "What If...?" none

Marvel stars you know, and love will also return to voice their characters such as Anthony Mackie as Captain America, Mark Ruffalo as Bruce Banner, Sebastian Stan as Bucky Barnes, Simu Liu as Shang-Chi, Haley Atwell as Peggy Carter and many more.

The trailer reveals three clones of The Watcher looming over our heroes and an ominous warning is declared: "This is where your story ends."

Prepare for a final watch when "What If...?" season three begins streaming December 22 on Disney+, with a new episode dropping daily for eight days.

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