Norman Stanley Fletcher, a career criminal, and his escorts – soft-hearted Mr Barrowclough and authoritarian Mr Mackay – make the journey on New Years Eve from London up to Slade Prison in Cumberland. One of seven different sitcom pilots commissioned by the BBC in 1973 ("Seven of One") starring Ronnie Barker. The plan was that the most successful would then be made into a full series. One of the episodes, "Prisoner and Escort", written by Dick Clement and Ian La Frenais, is this. Despite Barker's initial preference for another of the pilots, a sitcom about a Welsh gambling addict, "Prisoner and Escort" was selected. It was renamed Porridge, a slang term for prison; Barker and Clement and La Frenais actually came up with the same title independently of each other. (thetvdb.com)