on which network was it aired?
ITV's regional franchises ATV, Granada and Southern
The Secret Service
It was originally transmitted on the ITV regional franchises ATV, Granada and Southern, airing on Sundays at the regular time of 5.30 p.m. ATV and Southern showed re-runs until 1972 and Granada until 1975. Since then, the series has never been repeated in the UK.
what is "the secret service"? A 1969 British science-fiction television series
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The Secret Service [SEP] Broadcast
"The Secret Service" had a very limited distribution compared to earlier Anderson productions. It was originally transmitted on the ITV regional franchises ATV, Granada and Southern, airing on Sundays at the regular time of 5.30 p.m. ATV and Southern showed re-runs until 1972 and Granada until 1975. Since then, the series has never been repeated in the UK.