who are the voice cast?
Stanley Unwin, David Healy, David Graham.
The Secret Service
With the exception of Unwin, all voice actors on "The Secret Service" had supplied voices for earlier Supermarionation series. "The Secret Service" featured the voices of:


Supporting character voices were provided by all of the regular cast except Unwin, with additional contributions by David Healy and (for the final two episodes, "May-Day, May-Day!" and "More Haste Less Speed") David Graham.
what is "the secret service"? A 1969 British science-fiction television series on which network was it aired? ITV's regional franchises ATV, Granada and Southern who produced it? David Lane was any puppet used in the series? Yes - Father Stanley Unwin is a puppet character in the series
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The Secret Service [SEP] Voice cast
With the exception of Unwin, all voice actors on "The Secret Service" had supplied voices for earlier Supermarionation series. "The Secret Service" featured the voices of: Supporting character voices were provided by all of the regular cast except Unwin, with additional contributions by David Healy and (for the final two episodes, "May-Day, May-Day!" and "More Haste Less Speed") David Graham.