She is particularly known for her role in the British 1960s television series The Avengers, where she played the sexy secret agent Emma Peel. Her career in film, television and the theatre has been wide-ranging, including roles in the Royal Shakespeare Company between 1959 and 1964. Her professional debut was in The Caucasian Chalk Circle in 1955.
After The Avengers ended she returned to the stage, including playing two Stoppard leads, Ruth Carson in Night and Day and Dorothy Moore in Jumpers. A nude scene with Keith Michell in Abelard and Heloise led to a notorious description of her as 'built like a brick basilica with too few flying buttresses'. In 1986, she took a leading role in the West End production of Stephen Sondheim's musical, Follies.
In the 1990s she had triumphs with roles at the Almeida Theatre in Islington (north London), including Medea in 1993, Mother Courage in 1995, and Who's Afraid of Virginia Woolf in 1996. On television, she has appeared as Mrs Danvers in Rebecca and as the amateur detective Mrs Bradley in a series of mysteries.
She was created CBE in 1987 and knighted in 1994. Dame Diana was born in Doncaster in Yorkshire and lived in India between the ages of two and eight. She was married to Menahem Gueffen, an Israeli painter, from 1973-76, and to Archibald Stirling (a.k.a. Archibald Hugh Stirling of Keir), a theatrical producer, former officer in the Scots Guards, and a member of one of Scotland's grandest families, from 1982-90. By Stirling she has a daughter, Rachael Atalanta Stirling (b. 1977), who is also now an actress.