[1] The series was initially a medical drama that originated from the fictional rural town of Dixon Mills, where a young physician, Dr. Simon Locke (played by soap star Sam Groom), arrived in town to assist veteran physician Dr. Andrew Sellers (played by veteran actor Jack Albertson).
The series also featured guest stars such as William Shatner, Leslie Nielsen, Donald Pleasence, Michael Ansara, Martin Sheen, and Keenan Wynn.
https://www.tvpassport.com/tv-listings/stations/retro-tv-network/14646/2023-12-30 Most of the filming of the original season one episodes set in the fictional town of "Dixon Mills" took place in the village of Kleinburg, and surrounding Nashville and Vaughan areas of Ontario, often along more rural countryside roads.
A number of episodes featured scenes filmed along Kirby Road and at the bowstring arch bridge by the Humber River in the Nashville Conservation Reserve.
Some episodes were also filmed at the Valley Halla Estate on the Toronto Zoo grounds, and featured the house as the doctor's office and residence building.