One of the many reasons that the Marvel Cinematic Universe is so beloved is that its movies tend to provide heart-warming secondary characters in addition to its marquee heroes—characters that the movies aren’t quite about—resulting in a desire from the viewer to learn more about them, which adds appeal to the next marquee movie which they feature in.
Agent Coulson was the first and most powerful instance of this in the MCU, and we saw Joss Whedon utilize the audience’s fondness for him with devastating effect in Avengers. Rhodey was another, Rocket was even more so, and Falcon was as well, but aside from them and Coulson, the character MCU fans have probably wanted to learn the fate of with the greatest urgency was Agent Peggy Carter, left behind after the first Captain America film.
Captain America: The Winter Soldier eventually filled us in on her fate (again with devastating effect) but now we get to see the decades that became between those Captain America movies, the decades that consist of Peggy’s entire life. And it makes her eventual fate all the more painful, because if the first two episodes of Agent Carter are any indication, learning about Peggy’s post-Cap life is an experience of sheer delight.
[“I remember when I used to strap a chair to my ass and take a walk around the neighborhood.”]