Deadline Hollywood is reporting that Disney and Marvel Studios are in "the very early stages of development" for a new TV series based on Peggy Carter, Captain America’s lady friend, who was played in Captain America: The First Avenger by Haley Atwell.  Atwell also portrayed Agent Peggy Carter in a one-shot short film that will accompany the Iron Man 3 DVD that is due out next Tuesday, and it is this short (see the clip above), which focuses on her life as she starts a new career as a secret agent after the disappearance of Cap, who was frozen in ice after a Greenland plane crash, that will supposedly form the basis for the Agent Carter TV series..
As Deadline’s Nellie Andreeva points out, The Marvel Agents of S.H.I.E.L.D. TV series also started out as a short film that included as an extra on The Avengers’ home entertainment release.  According to Deadline, the project is current "in very early stages" of development, and there is no certainty that Atwell would reprise her role for a TV series, though she does play Peggy Carter in the short film, which was directed by Marvel Studios’ co-president Louis D’Esposito and included with the IM3 DVD.
A Marvel-based series with a female lead would be a good fit for ABC’s current schedule, which features a number of dramatic series such as Castle and Nashville with strong female protagonists.  So far the evidence indicating that the notoriously secretive Marvel Studios is indeed working on an Agent Carter TV series is circumstantial, but Deadline’s Andreeva claims to have source that confirms that the project is indeed in development with the studio currently looking to "lock in a writer" for the show.