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".
Barlow only returned to TV screens in Second Verdict (1976) after this series closed. It had, however, been planned and announced that the detective would be sent to Sydney, Lightning Ridge and New Zealand next, in the hour-long "Barlow Down Under", set to begin filming as an BBC/ABC/NZBC co-production in September 1975. Writer Elwyn Jones later reworked the story in 1977 for Weidenfeld & Nicolson Books, under the same name, as his fourth Barlow novel. A copy is held by the National Library of New Zealand.