Stephanie McCarthy was raised in the 'west coast' town of Port Lincoln, and her experiences there of the dangerous coastline and country life provided a background for her novel Diary Z. As a teenager herself, Stephanie lived for a year in the southern Philippines, before returning to South Australia to study drama at Flinders University in 1968. After two years, she left without completing her Arts degree in order to start a family. Over the next ten years, she wrote short stories and plays while bringing up her two children.
She re-enrolled at Flinders University and completed an Honours degree in Writing for the Stage and Screen. From then, on she wrote and edited for the screen, being involved in such feature films as Coda, Fever, The Dreaming, and Strangers. In the late eighties and into the nineties, Stephanie was also writing radio plays for the ABC and the BBC. Her television series Goldspinner was produced by the ABC. In 1993, Stephanie returned to Flinders University, this time to complete a Diploma of Education. From then on, she taught and wrote across the spectrum of the media. For a short time, she lived in Melbourne where she taught creative and professional writing at the Council of Adult Education, and she also wrote book reviews for The Advertiser. In 1998, her short story 'Edge of Colours' was broadcast on the BBC World Service. In 2001, her biography of her father, Bloody Marvellous: The Story of Dr. Norman Wicks, Country GP and Opthamologist, was published.
Stephanie re-married and took up an almost rural life in the Adelaide Hills with her husband, a graphic designer. Apart from visits to schools to give talks and run workshops, she writes full time. She is a committee member of the Australian Writers' Guild, and runs a monthly discussion group called Film Café. Two of her feature films have been supported by the South Australia Film Corporation and she made a return to theatre with her play 'Frank'll Kill Me' as part of the Festival of One.