Patricia Highsmith was one of the most successful suspense writers of the 20th century. Known especially for her novels The Talented Mr. Ripley, Carol and Strangers on a Train, she created complex and alluring characters, capable of terrible things and at the same time deeply human. Yet for much of her life, Highsmith herself remained an enigmatic figure, often seen as eccentric, troubled and difficult. But she had a circle of close friends who were loyal to the end.

Presenter Bridget Kendall is joined by Andrew Wilson, author of the first biography of Highsmith, and Vivien De Bernardi, a close friend of Highsmith's during her later years in Switzerland.

Produced by Jo Impey for BBC World Service

Image: Patricia Highsmith at her home in France, 1976