Smulders is best known for starring on the sitcom "How I Met Your Mother" and was loosely referenced in connection to an unproduced Wonder Woman film when Avengers director Joss Whedon was attached. (He included the note "Sorry, Cobie" in his announcement that he was off the project).
Comic book readers will be aware of Hill’s role in the Marvel Universe as Nick Fury’s second-in-command who took over as Director of S.H.I.E.L.D. when Fury went missing during the "Civil War" storyline. Maria Hill has also appeared in the Ultimate Universe (where Fury resembles Samuel L. Jackson) but in a different capacity, and she’s appeared in a couple of the cartoons as well, most recently voiced by Kari Wührer on "The Avengers: Earth’s Mightiest Heroes."
The Avengers will hit theaters on May 4, 2012.