What if one simple decision changed the course of history forever? That’s the question that Marvel’s What If…? explores as it looks at various scenarios around the Marvel Cinematic Universe. The premiere episode of the new animated series debuted on Disney+ today and it introduces us to Captain Carter, who takes the place of Captain America because of one simple decision.

The episode opens up with an introduction to the show’s concept from The Watcher, who explains that a simple decision can branch out into infinite realities and create alternate worlds. We then get a summary of the origin story of Captain America but The Watcher explains that a single choice could change everything and we see Agent Carter decide to stay by Steve’s side during the creation of Captain America as opposed to waiting in the booth.

Her decision to do that leads to the Hydra agent detonating explosives before Steve becomes Captain America. Steve gets shot before Peggy takes down the Hydra agent. A Colonel demands that someone take his spot and become the super solider and Peggy jumps in. The process of course works and Peggy become Captain Carter.

The Colonel is unhappy with the result of Peggy becoming the only super soldier and informs her that the best case scenario is that her blood could eventually lead to the creation of more soldiers. Frustrated, Peggy beats up a punching bag before having a conversation with Steve, who survived the gun shot but is rehabbing, about what she’s meant for. The two have almost the same conversation they had originally about looking for the right dancing partner. Despite the changes to the world around them, it appears Steve and Peggy are meant to be together no matter what.

We see a recreation of the scene from Captain America: The First Avengers in which the Red Skull discovers the Tesseract. After being told to stay out of the field by the colonel, Peggy and Howard Stark take matters into their own hands and Stark gives her the costume and shield.

Peggy stops the convoy of Hydra vehicles delivering the Tesseract and captures Arnim Zola. She delivers the Tesseract to the colonel and Stark uses it to build some kind of giant project. Peggy and Steve plan a rescue mission for Bucky and the 107th, who have still been captured by Hydra, though it doesn’t appear Bucky has been experimented on like before. Peggy calls for air support an Steve shows up in the Hydra Stomper armor Stark used the Tesseract to build. Together, they completely their mission successfully.

We then get a montage of Peggy’s successful missions as Captain Carter before we see the Red Skull in his ominous castle. He betrays the Nazis, much like he does in the film, only this time his plan is to recover the Tesseract and summon “Hydra’s champion.”

Peggy and Steve share a moment in a bar before being interrupted by Stark and Bucky who have their next mission. They plan to hijack a Hydra train, much like in the movie, but this time the Red Skull is supposed to be on the train himself and this could be their chance to end the war. Unfortunately, it’s a trap and the train is blown up with Steve inside.

Peggy interrogates Zola and gets the Red Skull’s whole plan as well as his location. Peggy rallies the troops and gets them to agree to storm the Red Skull’s castle. They take out the guards outside while the Red Skull uses the Tesseract, which he recovered from the remains of the Hydra Stomper, to open a portal and summon his champion.

Bucky and the Howling Commandos find the Stomper while Peggy and Stark find the Red Skull, who is now watching giant tentacles enter the room through the portal. A tentacle grabs the Skull and crushes him. We never get a name for the creature but it appears as though it could be Shuma-Gorath, an interdimensional creature with very similar tentacles.

Bucky finds Steve, who survived again somehow, and helps him into the Hydra Stomper. The creature continues to make its way out of the portal and tear part the room. Stark gets to work on closing the portal while Peggy does her best to fight off the creature. Steve arrives just in time to save Peggy but the creature quickly overwhelms them. Stark can’t close the portal because the creature is holding it open and Peggy decides to sacrifice herself by pushing it back into the portal herself, mirroring Captain America’s sacrifice. Peggy and the creature disappear and the portal is closed, leaving Steve and Stark alone with the Tesseract.

We then jump ahead to see a portal opened and Peggy comes flying out. She is greeted by Nick Fury and Clint Barton, who inform her that the war ended almost 70 years ago. She shows a look of disappointment, again mirroring the end of Captain America: The First Avenger.

The Watcher closes out the episode by explaining that Peggy’s simple choice to stay in the room gave the multiverse a brand new hero. He also explains that these are his stories but he cannot interfere because he is simply The Watcher.

This was a great start to this exciting new series. It was a great decision to kick of the show with this particular story because we are more or less starting from the beginning of the MCU history. This unique story, combine with the fantastic animation and returning cast of beloved actors, makes this a must-watch for any fan of the MCU.

You can watch Marvel’s What If…? on Disney+ now.

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