Spike and Lynda's relationship in the series grew out into a real one for Julia Sawalha and Dexter Fletcher. They were an item for several years and even lived together before going their separate ways.
A follow-up TV movie has several times been planned. In the mid-1990s a complete script, called 'Deadline' (not to be confused with the first series episode of the same name) was drawn up, but fell through. Writer Steven Moffat and a number of the cast members continue to express interest at a follow up.
Season 1 was filmed on location. However season 2 was filmed at Pinewood Studios in a reconstructed set, adjacent to the Gotham City set for Batman (1989) that was filming at the same time. This was due to the building in which the series had been filmed being demolished as part of a redevelopment. This is also why you do not see the exterior of the building from here onwards, except in stock establishing shots.
One of the show's most unique features is the characters' voices talking over the end credits. It was discontinued after Season 2 because Steven Moffat felt it wasn't working as well as it did in Season 1. Also, the actors grew fed up of showing up for the recordings because it meant they had to come in on the weekend.
Julia Sawalha (Lynda Day) and Dexter Fletcher (Spike Thomson) are the only actors to appear in all 43 episodes of the series. In second place is Paul Reynolds (Colin Mathews), who appeared in every episode except How to Make a Killing (1989) and The Big Hello (1991).