Clark Gregg played FBI Special Agent Michael Casper on The West Wing.
He is perhaps best known for his role as Agent Phil Coulson, a role similar to that of Agent Casper, in Iron Man, Iron Man 2, Thor and The Avengers, which he later resumed in TV spin-off Agents of S.H.I.E.L.D.. He also starred on The New Adventures of Old Christine and wrote, directed and starred in the feature film Choke. He had previously guest starred on Aaron Sorkin's Sports Night, and was part of the ensemble cast of David Mamet's State and Main.