In this 2016 standalone prequel episode "Young Hyacinth", which may have intended to have been a back-door pilot leading to a prequel series, we learn more about the origins of Hyacinth's mindset. The family surname is finally revealed to be the Waltons. According to this episode, in the early 1950s, young Hyacinth Walton is working as a domestic servant for the Cooper-Smiths by day while living in a small canal cottage with her alcoholic father ("Daddy") and her three sisters (Violet, Rose and Daisy). Impressed by her eccentric employers, Hyacinth vows to escape her poor background and enter a world of the elegant upper class, thus leading to her ongoing behaviour seen in Keeping up Appearances, of "trying to climb the social (classes) ladder". Presumably, if the episode had become a series, it would finally have officially revealed just exactly how and why Richard and Hyacinth met and eventually got married, which continues to cause much debate and theories, even amongst the casual viewer.
This was produced as part of the BBC's Sitcom Season celebrating the 60th anniversary of Hancock's Half Hour (1956).
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Young Hyacinth attracted an audience of 4,140,000 viewers, placing it twenty-second in the rankings for BBC1 for the period 29th August - 4th September 2016.
This prequel episode, in original broadcast order, somewhat confusingly followed the actual final "Keeping up Appearances" episode, which was actually the Christmas special episode entitled "The Pageant", which itself was shown after the final episode of series 5. However, chronologically within the shared story universe, it makes perfect sense to consider this as the prologue episode to the entire "Keeping up Appearances". These 2 time periods can be considered mutual canon, as they are both written by Roy Clarke.