Complex sentence: In the first episode, "Goodbye Jenny Wren" Maggie refers to her son, Steve Forbes (but not by name) as having "taken off to Australia" and if he hadn't have done so she would not have volunteered to join the organisation.
Split into simpler sentences: In the first episode, "Goodbye Jenny Wren" Maggie refers to her son, Steve Forbes, as having "taken off to Australia". She said that if he hadn't have done so, she would not have volunteered to join the organisation.