A spin-off from Z Cars, the series had begun in 1966 as Softly,
Softly, the later, augmented title reflecting how, as part of the
production team's wish to keep up with real-life developments,
Stratford Johns, Frank Windsor and Norman Bowler were now part of "a
new kind of organisation within the police". The retained writers
included Robert Barr, Elwyn Jones and Alan Plater.
http://www.guardian.co.uk/stage/2009/feb/05/david-lloyd-meredith-obituary
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