Name the Artist: Can't Stop?

Questions

Famous Gills: Actor who played Fish on "Barney Miller" and "Fish." (gill, fish ... get it)?

Famous Gills: Name the Monty Python member who best fits this TV / Movies.?

Famous Gills: Plays Agent Dana Sculley on the "X-Files."?

Father mulcahy: "_____, the lord moves in mysterious ways, but you take the cake". To whom was he referring?

Features: "You can't handle the truth!"?