Even with the recognizable names of a resurrected Clark Gregg as Agent Phil Coulson, and 'ER' vet Ming-Na as an all-new character, ABC and Joss Whedon's forthcoming 'S.H.I.E.L.D.' TV series still remains something of a mystery.  Comprised of a team of all-new characters, that mystery hasn't abated as the 'S.H.I.E.L.D.' TV series has officially added two new names to its list  So, who in the Marvel universe might they be playing and where could we have seen them before?

ABC and 'The Avengers' director Joss Whedon's forthcoming 'S.H.I.E.L.D.' TV series continues to assemble.  Following the series' first original casting of Ming-Na as Agent Melinda May, The Hollywood Reporter claims that actors Elizabeth Henstridge and Iain De Caestecker have joined the cast in the roles of Agent Gemma Simmons and Agent Leo Fitz, respectively.

Said to be a science whiz and a technology expert, Simmons and Fitz are constantly observed to be together, just as often as they bicker with one another.  Even so, both respected agents are considered experts in their respective fields, and valuable assets to the team.

Directed by Joss, the ‘S.H.I.E.L.D.’ TV series will see the ‘Avengers’ director writing the script with brother Jed Whedon, with Jed’s wife Maurisa Tancharoen directing as well.  The series will be set within the Marvel Cinematic Universe of the films, but mostly tell its own stories independent of the upcoming films.  Recent reports put the pilot episode as filming in January, for a potential fall 2013 debut.

What say you?  Do the latest ‘S.H.I.E.L.D.’ TV series castings build your excitement for the project?  What Marvel universe characters would you like to see incorporated?

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