From TV Guide:
"As the White House comes to grips with the revelation of the NASA-shuttle leaker, Lou (Janeane Garofalo) persaudes Josh, who persaudes Santos, that the sagging Santos campaign must clean house. Meanwhile, CIA conspiracy theorist Charles Frost gets a dressing down from Kate about his "ambush" of C.J.; and Bartlet and Abbey meet Ellie's fiancé, a research scientist Bartlet calls "fruit-fly guy."
Major cast members listed in the credits are Martin Sheen, Richard Schiff, Allison Janney, Bradley Whitford, Joshua Malina, Stockard Channing, Mary McCormack, Jimmy Smits and Janeane Garofalo.
TVGuide.com also has poll asking which show was the most disappointing this season so far. "The West Wing" is one of the 10 shows on the list including Martha Stewart's "Apprenctice", "The O.C.", "Invasion", "Desperate Housewives" and others.