- At the urging of her parents, began tap-dancing and singing in bars in London's East End at the age of 7.
- Got her start with the Royal Shakespeare Company as an usher; made her Stratford debut as Peggy Ashcroft's understudy in As You Like It.
- First big-screen role came with 1968 British drama Inadmissible Evidence.
- Was co-creator, with Jean Marsh, of the landmark '70s British drama Upstairs, Downstairs, as well as the early-'90s BBC series The House of Elliott.
- Has played author Virginia Woolf a number of times, including stage and TV adaptations of her one-woman show A Room of One's Own, as well as the play Vita and Virginia.
- Was made a Dame of the British Empire in 2001.
- Played Judi Dench's sister for the second time in British drama Cranford (2007); the first was in a 1959 BBC adaptation of the 1911 Arnold Bennett novel Hilda Lessways.
- 1985, BAFTA Film Awards — Best Supporting Actress: Nominee
- 1995, Tony — Actress (Play): Nominee
- 2011, Emmy — Outstanding Supporting Actress in a Miniseries or a Movie: Nominee
- 2001, Screen Actors Guild Awards — Outstanding Performance by a Cast in a Motion Picture: Winner
- 2009, Golden Globe — Best Performance by an Actress in a Supporting Role in a Series, Miniseries or Motion Picture Made for Television: Nominee
- 2004, Tony — Actress (Play): Nominee
- 2008, Emmy — Outstanding Supporting Actress in a Miniseries or a Movie: Winner
- 1972, Tony — Actress (Dramatic): Nominee
- 1967, Tony — Actress (Dramatic): Nominee
- Arthur Thomas Atkins — Father
- Julian Glover — Ex-husband
- Bill Shepherd — Husband
- Annie Ellen Elkins — Mother
- Guildhall School of Music & Drama, London, England