Peggy Carter may not have any superpowers, but if you look at Captain America: The First Avenger, it’s as much of a heroic origin story for her as it is for Steve Rogers. In fact, in that regard it subverts one of the most overused tropes in the action movie genre: the fridged girlfriend. Instead of rescuing his love interest from a supervillain or having to avenge her death, Captain America’s motivation is tied up in the kidnap and eventual death of his friend Bucky. So while Peggy Carter is technically his love interest (or alternatively, Steve is hers), from a storytelling perspective she’s more like an authority figure than a traditional female romantic lead. And from the point of view of her life story, Steve Rogers himself is the “fridged girlfriend.” If you interpret the movie as Peggy’s origin story as a hero, Steve is the love interest who dies too young, inspiring for her to forge ahead with her life and become one of the founders of S.H.I.E.L.D., thus changing the Marvel universe forever.