Ronnie Barker drives the same Ford Zodiac Mk IV car (JOY 602K) in two different stories, "Spanner's Eleven" and "Another Fine Mess".
The series was to have been called "Six of One", leaving the way clear for a sequel, to be called "Half a Dozen of The Other", but the BBC required seven episodes.
The first two episodes were developed into successful series, Open All Hours (1976) and Porridge (1974). These in turn spawned sequel series Going Straight (1978), Porridge (2016) and Still Open All Hours (2013), as well as a film, a spoof documentary.
One episode which was not picked up by the BBC for a series was later developed by ITV for Clive Dunn under the title My Old Man (1974).