Diana Quick

At 77 years old, Diana Quick has this physical status:

Quick is perhaps best known for the role of Lady Julia Flyte in the television production of Brideshead Revisited. She received an Emmy and British Academy Television Awards nomination for her work. Quick has also appeared in many theatre, film and television productions. She made her stage debut in A Midsummer Night's Dream at the Open Air Theatre, Regent's Park, London, in 1959. She has appeared in many stage productions in the United Kingdom and the United States, including The Rivals (1965), Hedda Gabler (1968), Measure for Measure (1970), The School for Scandal (1972), Hay Fever (1973), The Duchess of Malfi (1975), Saint Joan (1977), The Skin of Our Teeth (1981), and The Good Person of Szechwan (1984). Other stage work has included roles in Shakespeare's Troilus and Cressida and Brecht's The Threepenny Opera.

In 2009, she portrayed Queen Elizabeth II in "How Do You Solve a Problem Like Camilla?", an episode of the television documentary drama The Queen. Quick had played the same character as a younger woman in Alan Bennett's stageplay A Question of Attribution, one half of his Single Spies double bill. She explained how she prepared for the television role:

Source