This special was taped on January 13, 1968, one of a series of themed Jack Benny programs. It is available on DVD.
Nine days earlier (March 11, 1968), "The Lucy Show" aired its final episode. Lucille Ball was already preparing "Here's Lucy" for the Fall.
The show usually seen in this time slot (Wednesday 10pm on NBC) was "Run For Your Life" starring Ben Gazzara. When the show returned the following week, it was their series finale.
In the opening, Danny Thomas tells Bob Hope that stingy Benny has Elizabeth Taylor and Richard Burton doing the station break. He is joking. The famous couple do not appear.
In his opening monologue, Benny notes that the show's carnival theme was inspired by the success of Danny Thomas' "The Wonderful World of Burlesque" (1965-67) and "Chrysler Presents The Bob Hope Show: Shades of Vaudeville" (February 1967).