This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Although generally assumed to be Welsh, he was born in London and educated at Ealing County grammar school. However, both his parents were Welsh. Drawn to the theatre from an early age, he nevertheless took the precaution of training as an osteopath, a profession he also practised in recent years.

The original theme music was, like Z-Cars, a folk-song arrangement by Fritz Spiegl. It was released as a single (credited to the London Waits) on Andrew Loog Oldham's Immediate record label in 1966. The character of John Watt would see one final solo appearance in the last ever Z-Cars, in September 1978. Stratford Johns left the Taskforce series in 1972 (Barlow had his own spin-off series Barlow at Large) and it continued until 1976 with Watt in command.The series was set in the fictional south-eastern English borough of Kingley (played by Rochester and the Medway area of Kent). This left the way clear for Watt to come out of Barlow’s shadow and take command in his own right, with the reliable assistance of Hawkins.

In 1970 the series title was changed to Softly, Softly: Task Force and Barlow was promoted once again, this time to Head of Thamesford Constabulary's CID Task Force. Watt accompanied him. But the following year Barlow went it alone when he was headhunted by the Home Office to take up a post in Whitehall with the Police Research Services Branch in the series Barlow at Large. Softly, Softly: Task Force plodded on without Barlow for another six years and although the scripts were of a superior quality there was always the feeling that 'that little extra something' was missing. In 1969, to coincide with the BBC's move to colour broadcasting on BBC 1, Softly Softly ended. The characters of Barlow, Watt and Hawkins were promoted and moved to the Southeast of England in a new series set in the fictitious town of Thamesford. Here, as a result of changes in criminal activities, the police force needed to develop a new approach. Taskforces were set up: these were groupings of police expertise and manpower drawn together for special operations in the region. This was a new series in its own right and it was simply going to be called Taskforce. However, as it starred three strong characters from a popular "brand" that the BBC was reluctant to drop, this new series was retitled Softly, Softly: Task Force. For Kenneth Branagh's Renaissance Theatre Company, formed in 1987, he undertook a European tour that included performing Hamlet in Elsinore, plus As You Like It and Much Ado About Nothing. He also played the Governor of Harfleur in Branagh's 1989 film of Henry V. Terence Christopher Gerald Rigby (2 January 1937 – 10 August 2008) was an English actor with a number of film and television credits to his name. In the 1970s he was well known as police dog-handler PC Snow in the long-running series Softly, Softly: Task Force. Find sources: "Softly, Softly: Task Force"– news · newspapers · books · scholar · JSTOR ( February 2007) ( Learn how and when to remove this template message)

At the end of Softly Softly, the main characters – Detective Chief Superintendent Barlow ( Stratford Johns) and Detective Inspector Watt ( Frank Windsor) – both applied for the role of head of CID at the newly formed police force, the fictional Thamesford Constabulary, which was said to be a product of amalgamations carried out during a recent reorganisation of the British police and is referred to as the third largest force in Britain.