 Series 2 (1965) had nine episodes, series 3 (1966) and series 6 through 8 (1968 through 1970) each had thirteen episodes, while series 4 (1966–67) and 5 (1967) both had fourteen episodes.After a three-year hiatus the ninth, final series was transmitted in November and December 1973, with eight episodes.An hour-long 25th anniversary show was broadcast in 1989, comically introduced as "full frontal radio".