Z-Cars further spin-off entitled "Second Verdict" in which Barlow and Watt looked into unsolved cases and unsafe convictions. Frank Windsor made a final appearance as Watt in the last episode of "Z-Cars", "Pressure", in September 1978, with Robins (John Phillips), the Detective Chief Superintendent from the original series who had risen to chief constable. Jeremy Kemp, Brian Blessed, Joseph Brady and Colin Welland also appeared, though not as their original characters. "Z-Cars" is incomplete in the archives. The period 1962–65 is reasonably well represented; though with big gaps. With the 1967–71 sixth series, when the programme was shown almost every week,
Z-Cars and Z-Victor 2. The title does not, as sometimes suggested, come from the cars used, Ford Zephyr and Ford Zodiac. The Zephyr was the standard traffic patrol car used by Lancashire and other police forces, while the Zodiac was only used for specialist tasks such as motorway patrol. "Z Cars" as an idea came to creator Troy Kennedy Martin as he listened to police messages on his radio while trying to relieve the boredom of being ill in bed with mumps. It was set in the fictional Newtown, loosely based on the modern suburb of Kirkby, one of many housing