Softly, Softly centred on the work of regional police crime squads, plain-clothes CID officers based in the fictional region of Wyvern, supposedly in the Bristol area of England. It was designed as a vehicle for Detective Chief Inspector Charles Barlow and Detective Inspector John Watt (played by Stratford Johns and Frank Windsor respectively) from the police series Z-Cars, which had just finished its original run in December 1965 (no new episodes were produced in 1966 but it was revived in a different format the following year). Joining them in the early series was Robert Keegan as Blackitt, the police station sergeant from Z-Cars, now retired and acting as a freelance helper. The series introduced characters like Sgt Harry Hawkins (Norman Bowler) who would become very popular and well known. Promoted to Detective Chief Inspector, Hawkins stayed with the show for its entire run.