The first two series were produced by Terence Williams. From the third series, Jonathan Alwyn was appointed as producer, with Chris Boucher acting as script editor. Series 4, 5 and 6 were produced by Geraint Morris. The series signature theme tune was composed by Derek Goom. Bob Cosford was the initial graphic designer, who matched the theme tune to the opening and closing graphics centred on a revolving police "star and crown" cap badge, which bore the familiar "E II R" device of English police forces, but in place of the force name around the blue circle, it instead featured the generic words "County Constabulary."