On Thursday morning a new trailer for Avengers: Endgame hit the internet, and for an action movie, it sure looks sappy. It seems that the Apr. 26 release will spend a generous amount of time showing Earth's Mightiest Heroes mourning their losses and wallowing in their feelings. And that doesn't just include the characters who got snapped in Avengers: Infinity War, but also losses from way back in the MCU timeline, like Steve Roger's (Chris Evans) love Peggy Carter (Hayley Atwell). There's a Peggy Carter voiceover in the new trailer, but that doesn't necessarily mean that she'll really appear in Endgame.
First, we hear Tony Stark's (Robert Downey Jr.) voice leaving a message for Pepper Potts, his fiance, then Peggy picks up the thread, reciting one of her lines from Captain America: The Winter Soldier. Over black and white images that flash back to when Steve first enlisted to serve in World War II and Peggy's funeral in Winter Soldier, she says, "The world has changed and none of us can go back. All we can do is our best, and sometimes the best that we can do is to start over."
Since isn't the first reference to Peggy in the previews for Endgame, fans are wondering if all this nostalgia could mean that Captain America and Peggy will reunite somehow in Avengers 4. Fans of the agent are ready.
But it's more likely that the flashbacks to Peggy are all teases because, well, Atwell herself has denied being a part of Endgame. While appearing with Christopher Robin costar Ewan McGregor in a video for Wired, Atwell responded to the question by saying, "Not that I know of." She and McGregor feigned gasps, as if she were hinting at Agent Carter returning in some other way. So never say never.
The last time fans saw Peggy chronologically was in Winter Soldier, when Atwell played the true love of Cap's life with the help of impressive effects and makeup. So one could deduce, then, that if Peggy were to appear in Endgame as the result of the Avengers traveling back in time to undo the snap, Atwell would definitely play the part, no matter the character's age. It's possible that Atwell could just be sworn to secrecy on the matter, keeping Peggy's appearance under wraps to shock fans.
Considering that time travel figures into numerous fan theories about how the Avengers might be able to bring back the half of the earth's population Thanos dusted in Infinity War, there are several departed characters that could reasonably come back. And now, some fans believe that the Endgame trailer shows the Avengers suiting up to venture into the Quantum Realm (from Ant-Man and its sequel), where time and space work differently.
Atwell doesn't appear in the cast list on the movie's IMDB page, but that doesn't mean much. Chances are good that audiences will at least see a flashback to the first Captain America movie showing the pair when they were together. Even if she doesn't appear again in the prime timeline, Peggy Carter is still a major part of MCU history.