Frank Sinatra had recently married Mia Farrow on July 19, 1966. It was a short marriage that ended with divorce in Mexico in August 1968.
Jodi Michaels, the second contestant, had been a member of the Metropolitan Opera's children's choir for four seasons, singing in operas such as "Tosca," "Turandot," "Wozzeck" and "Vanessa".
Lynn Castle, the first contestant, besides being Steve Allen's barber in Hollywood, was also a songwriter to singles such as '"Teeny Tiny Gnome" (1966) and the psychedelic rock "Lady Barber" and "Rose Coloured Corner" (1967).
This was "mystery guest" Frank Sinatra's first and only appearance on the show. After he was identified, producer Mark Goodson invited Sinatra to replace him as a panelist.