From the third season (1974) onwards, the series was simply named "Barlow".
The main character Barlow originated in Z Cars (1962) and then moved over to Softly Softly (1966) before this series. He also appeared in Jack the Ripper (1973) and Second Verdict (1976) where Barlow and Watt examined real crime cases.
The following episodes are missing from the archives: "Vindication", "Bullion", "Rat Run", "Contessa" and "Nemesis".