The Red Door - S1-E4
Continuity mistake: When Moss goes to show Roy the picture on the bottom of his mug, the first shot shows the mug on the desk to Moss's right. However, the next shot shows Moss picking up the mug from a different place on the desk, further to his left. (00:03:50)
The Red Door - S1-E4
Factual error: Richmond says that the song "Coffin Fodder" is track 4 on the Cradle Of Filth album that he gives as a gift at the funeral. In reality, it is track 9.
Answer: It's a joke on the "118" numbers in the UK. 118 numbers were used for directory enquiries and adverts for them on TV always tried to give a way to easily remember one for a particular company. The fake ad in the show takes it to the extreme. People in the UK do not use "911", the point of the joke was that Roy had forgotten "999" while saying it was easy to remember.