The Rivals of Sherlock Holmes (TV Show 1971) | The Assyrian Rejuvenator (S01E11)

Episode 11: Inflated claims about the powers of an expensive elixir put private investigator Romney Pringle in pursuit of a ruthless con man. The trckster has reason to believe that his customers won't complain, but Pingle sets out to destroy the crooked business.

Author: "Clifford Ashdown" (R. Austin Freeman and John Pitcairn)
Donald Sinden as Romney Pringle, reformed con artist

Episode 12: https://rumble.com/v72erpa-the-rivals-of-sherlock-holmes-tv-show-1971-the-ripening-rubies-s01e12.html