Well, it was bound to happen, wasn't it? Peggy Carter was depicted as being "super old" in Captain America: The Winter Soldier, so it makes sense that she'd be on death's door in the follow-up flick. There's also the matter of those leaked set photos from a couple of months back, in which a funeral - assumed to be Carter's due to the fact that her daughter, Sharon Carter (Agent 13), can be seen in prominent attendance - was seen being shot. And given that Captain America was also glimpsed alive in the leaked photos, the funeral clearly isn't his. Carter's death will certainly be a sad affair, but it's something we all probably knew was coming, given her age. It will also offer up a neat narrative arc for the Captain, grounding the film in a melancholy that feels earned. Still, she lives on in TV's Agent Carter, at least.