How much of the bigger Marvel Universe are you weaving in?
[Screenwriter/Co-Creator Christopher] McFeely: We can’t help but weave in the Marvel Universe. We’ve been at this for a few years now. All of our reference points are within the universe. We need a scientist character. We didn’t go very far to come up with Anton Vanko, just as a very small part scientist character. If you know what he is, or what he goes on to be, that’s interesting. If not, he’s the Russian scientist.
[Screenwriter/Co-Creator Stephen] Markus: Also, working in the past where you already know the future — obviously, we saw ninety-something old Peggy — there are references being made, whether you do them on purpose or not. We know Hydra eventually took over S.H.I.E.L.D. When somebody says something hopeful about the future in Agent Carter, that is going to be tinged with the fact we know the future didn’t work out that well. There are plenty of little indicators of the future going forward, and the legacy of both the S.S.R. and Howard’s technology that will have ramifications later.
It’s almost like the M. Night Shyamalan curse, though. Viewers always expect some crazy twist in his movies. With Marvel, people anticipate all these tie-ins to other projects.
McFeely: I suppose it has the red box on the front. It’s a Marvel project, so they are going to expect something. But we’ve really tried to make the best show, about an interesting character in a world where there are some glowing objects and where a superhero has died.
Markus: We are also slightly freed up from that interconnection by the period. On “Agents of S.H.I.E.L.D.,” Captain America and Iron Man and everybody are running around in that same world and same time period. They could theoretically show up at the door. There’s nobody around during “Agent Carter.” You can’t have an end-of-the-credits tag where Nick Fury shows up and talks to Peggy. He hasn’t been conceived yet. We’re a little cocooned.
– from an Interview at Comicbookresources.com