Hayley Atwell says Marvel explored a few different storylines for Avengers: Doomsday, and only a few made the cut.
"We tried different things, we shot different things, there were different storylines, some picked up, some developed, some dropped away," Atwell told The Playlist, careful to not reveal specifics.
Despite being absent from the initial cast reveal (which, if you recall, involved a livestream and several chairs), she made a surprise appearance during Marvel's big Hall H panel at SDCC 2026 that confirmed her involvement in Doomsday. Most recently, she appeared in a special Avengers: Endgame Encore post-credits scene alongside Chris Evans. In the scene, Loki travels back into the past and knocks on Steve and Peggy's door.
It wouldn't make sense for Steve Rogers to appear in Doomsday without Peggy, given that his decision to return to the past (rather than grow old and run for government like Bucky Barnes) was based solely on his desire to live out a full life with Peggy instead.
Atwell made her last MCU appearance in 2022's Doctor Strange in the Multiverse of Madness as a multiversal variant, known as Captain Carter, belonging to Earth-838. It was a short-lived cameo, however, as she was quickly killed by the Scarlet Witch (something that Atwell said was a "disservice" to her character).
Avengers: Doomsday hits US theaters on December 18, and in UK cinemas on December 16. Get up to speed on Marvel Phase 6 with our guide on how to watch the Marvel movies in order.
