Bradley Whitford is the 4th veteran of the TV series "The West Wing" to play a role on "In Plain Sight". The other 3 are Joshua Molina, Alison Janney, and Richard Schiff. Apart from series star, Mary McCormack, who is also a West Wing alum.
Bardley Whitford and Mary McCormack had also worked together in New York on the Broadway stage in 2008 with the revival of, "Boeing Boeing".