In this episode the Chief reveals that the "Cone of Silence" was invented by Professor Cone.
This two part episode is a sequel to "The King Lives?" from last season. The take-off of the movie "The Prisoner of Zenda" continues as Max once again switches places with his lookalike king (ala Ronald Colman) and James Caan appears as a swashbuckling villain inspired by the Rupert of Hentzau character played by Douglas Fairbanks Jr.
If you look closely during the scene were the Chief is making out with Gina in the park, 99 is wearing heels as she walks by. This is interesting due to the fact that for most of the series run Barbara Feldon wore flats so that she wouldn't tower over Don Adams, who was about three inches shorter than she was.
During the wedding vows we do not hear 99's real name as the Admiral's snoring covers her actual name that was said during the vows.
Although only two episodes ago Max chose Hymie as his best man, the Admiral fills the role at the actual wedding. Incidentally, the Chief gives away the bride.
Max and 99 inform the Chief of their engagement in this episode.