Gwynedd Robyns was born in Australia but raised in New Zealand, to which her mother returned on the death of Gwen’s father. She attended Wellington Girls’ College, where she was head girl. After graduation, she went to work on a weekly newspaper. In 1946, at age 28, she moved to London, where she quickly became a reporter for the Sunday Express. Six weeks later, she was the only woman among 40 male reporters on a press trip to Germany looking for the grave of a New Zealand war hero. On the trip she met Paul von Stemann, a writer for the Danish Berlingske Tidende, whom she married two months later. Gwen Robyns wrote a weekly “Letter from London” column that was eventually syndicated to 40 newspapers around the world. In 1948, she became the first women's editor for The Evening News, then the world’s biggest evening newspaper. Over the next nine years, she became widely known for her passion for human interest stories. Financial problems at home led her to seek extra money by writing books, most of them biographical; some were ghost-written for celebrity clients. Her first was David Hicks on Decoration (1966), a collaboration with the celebrated designer. Her book The Mystery of Agatha Christie (1979) won an Edgar award from the Mystery Writers of America.