Marvel Studios is taking a step into the unknown with production of several Disney+ series set in its blockbuster Marvel Cinematic Universe. But things are taken even a step further with What If...?, an animated anthology series based on the popular Marvel comic series that explores alternate universes.

Here's everything we know so far about Marvel's What If...?

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What is What If...?'s Plot?

Drax the Destroyer and T'Challa in Marvel's What If...?

What If is a comic series that premiered in 1977. It has run 13 volumes since then, most recently in 2018. The series asks questions about Marvel characters, such as, "What if Spider-Man had joined the 'Fantastic Four'?" and "What if Thor became a herald of Galactus?" The comics then play out the scenarios, sometimes offering multiple endings for fans to get a taste of what could have been.

The TV series, which is Marvel Studios' first animated show, will follow the comics' main idea. Every episode, Uatu the Watcher will take viewers through a non-canonical, alternate universe involving characters from the MCU. For example, the first episode has already been announced to show what could've happened if Peggy Carter had taken the Super Soldier Serum instead of Steve Rogers and became Captain Britain. Other episodes will follow T'Challa becoming Star Lord, Thor hosting a huge party, Gamora hunting down Iron Man, Spider-Man versus Marvel Zombies and Doctor Strange going on what looks to be an epic adventure.

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Marvel's What If...? Trailers

A first look at What If...? premiered in November 2019 as part of Marvel Studios: Expanding the Universe, which is available to watch on Disney+. It showed parts of several storylines, including the aforementioned Peggy Carter as Captain Britain, what looks to be Steve Rogers manning an Iron Man-esque suit, a zombified Captain America and T'Challa taking to space as Star Lord.

Another trailer for What If...? was later shown at Disney's Investor Day 2020. Along with expanded clips of the storylines mentioned above, the trailer also included shots of Nick Fury, Bucky Barnes, Iron Man, Hawkeye, the Collector and Captain Marvel, as well as Doctor Strange fighting an evil version of himself.

In June 2021, Marvel previewed a clip from the series as the Annecy Festival. The clip showed the scene in which Peggy Carter takes the Super Soldier Serum and becomes Captain Britain.

An official trailer was released a month before the series' premiere. It reveals a few new storylines, such as Erik Killmonger saving Tony Stark from being kidnapped in Iron Man, the Guardians of the Galaxy fighting alongside Thor in a dilapidated city, the Hulk facing off against many opponents at once, Loki facing someone with his own army, Peggy Carter meeting Doctor Strange, Peggy fighting a giant tentacled monster and T'Challa and Yondu fighting the Collector. There are also some glimpses of Vision, Howard the Duck, Spider-Man, Ego, Zombie Iron Man and what looks to be some Ultron bots.

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Which MCU Characters Are in What If...?

What If...? is created and run by A.C. Bradley, who is known for her work on the Trollhunters: Tales of Arcadia series. She also serves as the head writer. All episodes were conceived and written by her, story editor Matthew Chauncey, series director Bryan Andrews, executive producer Brad Winderbaum, junior executive Simona Paparelli and script coordinator Ryan Little. Director Andrews is a storyboard artist who has worked on 12 MCU films, including all four Avengers films, Doctor Strange and Ant-Man. Ryan Meinerding, the head of visual development at Marvel Studios, worked with Bradley to develop a cell-shaded animation styles for the series based on the characters from the films.

At 2019's Comic-Con International in San Diego, Marvel Studios President Kevin Feige revealed over twenty actors from the MCU who would be reprising their characters for roles in the animated series. The list includes Josh Brolin (Thanos), Chris Hemsworth (Thor), Tom Hiddleston (Loki), Samuel L. Jackson (Nick Fury), Jeremy Renner (Hawkeye), Paul Rudd (Ant-Man), Mark Ruffalo (Hulk) and many more. Additionally, veteran actor Jeffrey Wright will play The Watcher, and the cast has grown to include Benedict Cumberbatch (Doctor Strange), Don Cheadle (War Machine) and Clark Gregg (Agent Phil Coulson). Bradley has confirmed that there will be multiple surprise cameos from other MCU actors and characters. The series also features the final MCU performance of the late Chadwick Boseman (Black Panther).

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When Marvel's What If...? Will Be Released

Howard the Duck in Marvel's What If...?

What If...? was initially announced to premiere during the first year of Disney+. However, Feige revealed during San Diego Comic-Con 2019 that the series will air its first season in the summer of 2021, with episodes airing weekly.  In December 2019, Feige announced that a second season was already in pre-production. Originally slated for ten episodes, Winderbaum has since said that one episode has been pushed to Season 2 due to pandemic-related reasons. As a result, both seasons will now consist of nine episodes. The series will premiere on Aug. 11, 2021.

This article will be updated as more information becomes available.

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