The long wait for Marvel Studios' What If...? series is coming to an end. This highly-anticipated show is expected to premiere on Disney Plus on August 11, 2021. While the advertising for the series has pushed fan-favorite characters like Peggy Carter and T'Challa to the forefront, many more clues were revealed in the What If...? trailer.

What If...? is based on a comic book anthology with the same name that first debuted in 1977. It follows an alien known as Uatu, or the Watcher, as he digs into alternative realities and watches canonical storylines unfold with a few major changes. These one-offs often alter the defining characteristics of characters and force them to question their morality in brand-new ways. It's not afraid to pit friends against each other and change the results of major conflicts. Many times, the stories end with a tragic reveal or death.

Related: Everything We Know About The Upcoming MCU ‘What If...?’ Series

Marvel Studios is putting their own twist on the comic book, running What If..? as a 10-episode animated series. It will feature the voices of iconic actors in the Marvel Cinematic Universe. Joining the cast to voice Uatu is Westworld's Jeffrey Wright. Along with familiar cast members like Josh Brolin and Haley Atwell, the late Chadwick Boseman will be heard playing T'Challa for one last time.

Earlier in July, the trailer for the What If...? series was released, garnering tons of speculation about what storylines the series will dive into. Here are four epic storylines that were teased in the What If...? trailer.

Zombies? Avengers? That's a bit out of the ordinary as these two groups usually have opposite priorities. The brief clips of the zombified Avengers were a standout portion of the What If..? trailer. Quick snaps were shown of both Captain America and Iron Man with the added aggression of being undead.

This storyline arises from Marvel Zombies, a five-issue comic book run created by The Walking Dead's Robert Kirkman and Sleeper's Sean Phillips. It takes place on Earth 2149 (the Marvel Cinematic Universe is dubbed Earth-199999) where the Avengers are existing as zombies who were affected by the "Hunger." Through their journey, it is revealed that many of their core characteristics remain the same, however, they are deeply affected by their craving for human consumption. The comics are just as traumatic and entertaining as it sounds, leading many fans to erupt with joy upon the hint of its appearance in this upcoming series.

This is certainly an odd one. T'Challa's arrival in the trailer startled viewers for a reason far beyond his appearance as Starlord. The trailer also featured the late Chadwick Boseman's voice, a sound that many fans have been yearning for. What If...? is expected to be Boseman's last posthumous project.

In the trailer, his character was seen traveling through space with Guardians of the Galaxy's Yondu. Therefore, it can be assumed that in this alternate reality, T'Challa is not the Black Panther, and instead, he is Starlord. Not much is known about this specific plot arc that Marvel Studios has decided to pursue but it could shape up for a lot of interesting quips, as the two superheroes have polar opposite characteristics.

Voiced by Seth Green, Howard the Duck had a few noteworthy cameos in the Marvel Cinematic Universe. He had brief appearances in both Guardians of the Galaxy movies and he reappeared in the fight against Thanos at the end of Avengers: Endgame.

While it is unclear what he's doing in the What If..? series, it can be expected that he'll play a substantial role due to his conspicuous appearance in the trailer. He looks like he could be playing a rather important figure as he is dressed in a dark purple suit and is seen with very ominous facial features in the trailer.

It's about time for Peggy Carter to get the attention she deserves. Captain Britain is a storyline that has been teased since the beginning of What If..?'s press circuit. In this series, Captain America and Agent Carter actor Hayley Atwell will be returning to the screen to reprise her infamous role. As time ticks by, more and more details have been released about this arc. Back in June, a top-secret clip of Peggy's transformation was shown at a Women in Animation panel. Deadline reported, "Today’s clip showed off more of Peggy Carter’s transformation into Super Soldier Captain Britain, replete with her Union Jack-emblazoned shield, and also featuring Steve Rogers and Howard Stark."

It is intriguing to suspect how this will play out and if Marvel Studios will use this time to continue the love story between Steve Rogers and Peggy Carter, but with the added change of power dynamics. While Marvel Studios may have been over-fluffing this storyline, a bit, it's definitely highly-anticipated and is shaping up to be a showstopper.

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