This review contains spoilers for episode 1 of What If...?.

Marvel’s latest streaming series is a totally different kind of show. There were plenty of things that made WandaVision, The Falcon and the Winter Soldier, and Loki unique, but they ultimately felt like MCU movies stretched out across a few weeks. What If...? is both the MCU’s first animated project and its first animated series, exploring hypothetical scenarios for how Marvel storylines could’ve turned out differently with one little change. It’ll undoubtedly be the most alienating MCU project for outsiders and casual viewers, but there’s an abundance of Easter eggs for diehard fans.

The first episode, “What If... Captain Carter Were The First Avenger?,” now streaming on Disney Plus, reimagines Captain America: The First Avenger if Steve Rogers was critically injured right before receiving the Super-Soldier Serum and Peggy Carter took his place instead. Head writer A.C. Bradley’s script is briskly paced, packing in all of The First Avenger’s main plot points in a 30-minute runtime. It doesn’t waste a second and never feels like it’s rushing its storytelling.

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It was great to hear the voices of all the actors from the movies reprising their roles (well, most of them), but voice acting is a totally different beast than performing in live-action. It’s clear that some MCU stars are more adept at voice acting than others. Hayley Atwell gives an awesome turn as Captain Carter, but Sebastian Stan’s line deliveries are blander and less committed, possibly as a result of needing to record take after take of every line for the animators’ sake. Hearing a different voice than Chris Evans’ as Steve Rogers was initially pretty disappointing, but replacement actor Josh Keaton ended up nailing the role.

Peggy takes the Super Soldier Serum in What If

The animation of What If...? is both stylish and engaging. Its sharp 2D visuals give the impression of flicking through a comic book, but the images never feel flat because the animators’ impressive portrayal of light gives each scene plenty of depth.

Marvel’s live-action shows have featured a bunch of explosive action sequences, like the final battle in The Falcon and the Winter Soldier and slaying Alioth in Loki, but they still ultimately felt like TV action on a TV budget compared to the large-scale spectacle of the franchise’s big-screen output. Being animated has allowed What If...? to explore huge, extravagant set pieces that a live-action TV budget couldn’t accommodate. Captain Carter punches German planes out of the sky and takes on an interdimensional octopus.

The Watcher in outer space in Marvel's What If

The anthology format of What If...? is anchored by Jeffrey Wright as “The Watcher,” an intergalactic observer keeping an eye on the multiverse while vowing never to interfere in its events. The Watcher’s voiceover frames the narrative like Rod Serling in The Twilight Zone, providing a brief introduction at the beginning and wrapping everything up at the end. Marvel couldn’t have picked a better narrator than Wright, whose rich, captivating voice sells the cosmic gravity of the stories he tells.

“What If... Captain Carter Were The First Avenger?” pretty much retells the plot of Captain America: The First Avenger with a new hero. Some scenes are shot-for-shot recreations of familiar First Avenger scenes with Peggy in Steve’s place. The episode works best – as will all What If...? episodes – when it digs into what makes Peggy’s Super-Soldier career different than Steve’s. It explores the challenges a female Captain America would face after The Falcon and the Winter Soldier explored the challenges a Black Captain America would face.

Captain Carter preparing to fight in Marvel's What If

Captain Carter faces prejudice from sexist soldiers on both sides. Bradley Whitford’s smarmy Allied colonel initially refuses to let her go out in the field because she “might break a nail” fighting on the frontlines. A hulking German troop calls her a “fragile Fräulein” right before she beats him to a pulp. Thanks to the episode’s stellar action scenes and Atwell’s empowered performance, these characters quickly eat their words.

The greatest moment from the pilot episode is a montage of Peggy kicking Nazi butt with Steve’s Stark-powered assistance. The violent visuals are brilliantly juxtaposed against ‘40s-style big band music. The fight scenes are timed so the shield smackdowns land at the same time as the cymbal crashes. Fans are in for some really exciting sequences throughout What If...?’s run if this is just the tip of the iceberg.

Captain Carter and a group of soldiers looking at Hydra Stomper in What If

There are a few key differences between What If...?’s alternate take on The First Avenger and the actual movie. The episode shakes things up when Howard Stark turns Steve into an early version of Iron Man powered by the Tesseract, or “Hydra Stomper,” turning a solo superhero story into a team-up. In this version, Steve is the one presumed dead after the train set piece, not Bucky, but that’s still essentially the same thing – it gives the hero a personal vendetta against Hydra.

The finale is totally different, as Hydra manages to open up an interdimensional portal with the Tesseract that unleashes a giant, tentacled Lovecraftian beast. But this is just a different sacrifice with the same result. Instead of crashing into the ice after making a date with Steve, Peggy leaps through the portal and ends up in S.H.I.E.L.D.’s headquarters in the present day.

Captain Carter, Bucky Barnes, and Dum Dum Dugan looking up in Marvel's What If

It was more than just a fun gimmick to see Peggy’s Cap in action. She makes for a genuinely great superhero, with the perfect combination of well-timed one-liners and impressive ass-kicking. With any luck, this won’t be the last What If...? episode set in the universe where Peggy became the first Avenger, and future installments will explore how the Battle of New York, the Sokovia Accords ordeal, and the last stand against Thanos would’ve turned out if Earth’s mightiest heroes had a different, but equally competent leader.

All in all, What If...? has gotten off to a terrific start with “What If... Captain Carter Were The First Avenger?” But aside from swapping out Steve for Peggy and bringing the Iron Man technology forward a few decades, it pretty closely follows the familiar plot of the movie its timeline deviates from. Hopefully, this won’t become a pattern and the upcoming episode that sees T’Challa becoming Star-Lord won’t just remake Guardians of the Galaxy with a different lead character.

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