He substituted for Sebastian Cabot, as the gentleman's gentleman, or butler, for Brian Keith's Bill Davis character, in the sitcom Family Affair (1966). This was during Cabot's eight episode leave of absence (plus one overlapping episode, where they both appeared) from the program, after Cabot developed pneumonia in 1967. Williams portrayed the part of Mr. Giles French's brother, Nigel ("Niles") French.
