Novellist R.D. Wingfield, whose "Frost" book were the inspiration for the series, was very critical of the TV adaptation and said that it had ruined the character of Jack Frost that he had created in his novels.
Frost was a chain smoker in the novels. In his 2013 autobiography "My Life" David Jason revealed they decided to make Frost a non-smoker in the television series as he had recently quit smoking cigarettes in real life.
Between takes, the cast (particularly David Jason) and crew were forever playing pranks on John Lyons (DS George Toolan). They devised fake scripts which Lyons had to learn at short notice, involving ludicrous situations for Toolan: on one occasion, they made his character wear a neck brace; on another, they made him ferret around in a smelly rubbish bin looking for evidence. Each time, Lyons said "You won't catch me out like that again" but he always fell for the next prank.
Two of the regular stars in this series are actors who have changed their names from White for professional reasons. Inspector Frost is played by David Jason (real name David John White) and his on/off girlfriend Shirley Fisher is played by Lindy Whiteford (real name Lindy White).
To prevent the show from becoming too formulaic, Frost had several sidekicks between cases, unlike most detective shows. It gave him new characters to bounce off and challenge his slightly set view of the world.
David Jason said Frost was a man who passed from his fifties deep into his sixties during the course of the show, and wasn't likely to be knocking his pipe out until four in the morning. He figured it was better to put his head in a paint pot for a couple of hours and wind down that way.
David Jason said the popularity of the show was based on a hunch that had well and truly paid off. He liked the darkness of the show after the lightness of Only Fools and Horses.... (1981) and The Darling Buds of May (1991) because it showed audiences he could play both, but lightness became a part of Frost too.
David Jason grew a mustache for the role. It was his idea, as he imagined Frost grew one in his youth to give himself a few extra years and more maturity. He lost the mustache between series to play other parts and than needed four weeks to grow it back as well as stop shaving at the right time ahead of shooting. Sometimes Jason missed the mark and had to help it along with a bit of "coloring-in"' but it was always ready for filming.
David Jason said he never would have been cast as Detective Inspector Jack Frost if he hadn't appeared in A Bit of a Do (1989) first, because it put him on Yorkshire Television's radar, which subsequently led him to The Darling Buds of May (1991) and than Frost.
When The Darling Buds of May (1991) came to an end, David Jason was asked what he wanted to do next, a new and exciting experience for him, because his television career had gotten so successful he could shout the odds on where his career went. He said he loved detective shows, and wanted to play a detective, which culminated in him getting the role of Detective Inspector Jack Frost.
When David Jason expressed an interest in playing a detective, five books, all crime fictions in different areas by different authors were posted to him. Jason took them on holiday to Florida and read them over the next fortnight by the pool. Before Jason settled on Detective Inspector Jack Frost, he considered a Sherlock Holmes type detective because it was different from anything else he had done. Jason called from Florida saying he wanted Frost.
David Jason said the show was "contemporary, clever, dark and revolved around unpleasantness like murders of drug addicts and robberies at strip clubs". Also, Frost was "shabby, bitter, caustic and a commanding character, unlike Pop Larkin".
Frost had to be cleaned up from the books, where Frost was a chain smoker, but David Jason recently gave up smoking. He used to smoke four or five cigarettes a day, or in the evening with a drink, and didn't want to start again, and smoking was taboo on TV in 1992. Frost was made a former heavy smoker who had just quit, making him grumpy and irritable around people who still did.
There was a courtroom spin-off considered called "The Usher" but within three months of the end of the show, Yorkshire Television changed hands and amalgamated with ITV, so "The Usher" never went ahead.