Of the seven primary cast members, Patricia Routledge, Clive Swift, Judy Cornwell and Geoffrey Hughes appear in all 44 episodes. Josephine Tewson (Elizabeth) was close behind, appearing in all but one, "Golfing with the Major". Shirley Stelfox appeared as Rose in series 1, while Mary Millar held the role from season 2 onwards. Similarly, David Griffin (Emmet) did not appear until series 2, and appeared in but two episodes from that point onwards.
Bog off, Onslow!
In most episodes following the introduction of Emmet, he is frequently seen to stare out the side living room window of Elizabeth's house at the assorted goings-on next-door at Hyacinth's. However, all exterior shots of the house clearly show that there are no windows on that side of this room.
During the end credits, we see a table set for a posh dinner. When all credits have been shown, Hyacinth is shown rearranging a fork and a spoon and then putting a name plate on the table. As the camera zooms in on it, you can see that it reads Harold Snoad and the words "Produced & Directed by" appear above it (plus a copyright notice below it).