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 Other British actors who played regular roles in the early years included Joss Ackland. Although he played no regular role in the series, future Monkee Davy Jones appeared in three episodes. John Thaw, later in "The Sweeney" and "Inspector Morse", appeared in four episodes in 1963 as a Detective Constable who had to leave the force because he had a "glass head" – he couldn't drink alcohol when socialising and mixing with the criminal fraternity, very much part of a detective's job. "Z-Cars" ran for 801 episodes. The original run ended in 1965; Barlow, Watt and Blackitt were spun off