I don't remember what I was doing the first time I saw a commercial for "Agent Carter" but I knew I had to watch it. If you know your Marvel on screen history, Agent Peggy Carter first appeared in the "Captain America: The First Avenger" movie as she is from the olden days when Captain America was just becoming a super hero. This show is set as such and any time you can have a good show set in a time period that isn't being explored by television already (See: "Galavant") I'm ready to watch it. We already have "Marvel's Agents of S.H.I.E.L.D." so we don't need a modern television series like this.
The fact that this is set in the past comes into play a lot, most noted is the presence of Tony Stark (Iron Man)'s father Howard Stark. It's a unique opportunity to see how not only some of these modern characters developed but how some of their parents and everything were. (One episode did have Whiplash's dad in it) On top of that it's got a lot of action, some humor and is overall a detective show set in a time period without Google.
Season One (as a mid-season replacement I suppose) was a mere eight episodes but this could be a hit and have the longevity to match any other show on television right now. One of the biggest factors in this show of course though is that the lead character, the star of the show if you will, is female and that just makes it all that much better. At the time this show takes place, it is a very interesting time for women as they are still thought to be less than men in the way that you could say "Listen lady, a dame's place is in the kitchen not as a cop" and get a laugh from your fellow employees rather than a lawsuit.
In the Marvel Universe, Peggy Carter lives a long life and if you follow the movies then you know how she dies. This is to say that no matter what kind of trouble Agent Carter gets into during the course of this show, you know she's going to make it out alive, but that just begs the question as to whether or not a series would kill off their main character anyway.
Pretty much anything Marvel does at this point is something that I need to watch and even though this doesn't have Joss Whedon behind it, "Agent Carter" is still a show that is worth investing your time into. If you really think about it, from the first time we see Peggy Carter to the last time we see Peggy Carter in the Marvel Universe, there is quite a large gap that can only be filled by more episodes here. Oh, and comic books too.