This was the first episode broadcast on CBS.
In the previous seasons Barbara Feldon was in the credits as "#99". In the credits for Season five she is just listed as "99".
Max, 99 and the Chief are seen walking on the Moon, where the Chief informs Max and 99 that this will likely be their last secret meeting on the Moon because, "Now that the astronauts have landed successfully, there will probably be a lot more of them coming." This was in reference to the Apollo 11 Moon landing which had occurred just two months prior to this episode's air date.
Martin Landau briefly appears as Maxwell Smart after having his face altered to hide his identity. Landau played Rollin Hand on the Mission Impossible TV series for the first three seasons. Rollin Hand was a Master of Disguise.
The title 'Pheasant Under Glass' is a way of serving the Poultry Dish using breast meat, wine sauce and served under a glass dome.