Originally Posted by Ksb36
Remember in the comics Peggy was a blonde, too. We all need to remind ourselves that the Marvel movie universe is not the Marvel comics universe. Nowhere I repeat nowhere has it been stated that EVC is playing Sharon Carter--only that she's Agent13. There's no rule that states that Agent13 is SC in the Marvel movie universe. Feige has been VERY flexible with the comic tropes (cough--Mandarin, anyone?) and based on all the evidence taken together it does not look like EVC has a very big part.
Clearly I may be wrong. But all the evidence points to HA having a very substantial part and based on the sheer numbers of characters in TWS, it seems most likely that she is indeed SC.
I don't see how they're not going to eventually reveal EVC as Sharon Carter, due to them doing as many auditions as they did for the role and them being sort of secretive about her true identity. Only other famous female SHIELD agent out there is maybe Mockingbird but I don't see how she'd really fit into the WS storyline.