Kim Cattrall's mum, Shane, never saw her father again after he left in 1938, but the actress was stunned to find out the truth behind Baugh's disappearance - he walked away from his family to start a new life with another woman.
During the historical show, which aired on Friday (25Feb11), Cattrall learned Baugh wed Isabella Oliver in August 1939, a year after meeting, and they lived in a village just three hours away from his existing family.
The couple went on to have four children, with the youngest, George Baugh, born in 1959 - three years after Shane gave birth to Cattrall.
Admitting she was "disappointed" by Baugh's adultery, the star said, "That son of a b**ch. He was a bigamist... I knew he was gutsy, but now... he was a criminal. He left in 1938; within a year, he was remarried."
Kim Cattrall's grandfather later emigrated to Australia before passing away in 1974, without ever getting back in touch with the family he had left behind.