In 1983, Celia played a servant in Michael Winner's remake of the Margaret Lockwood classic The Wicked Lady. Her co-stars included Faye Dunaway and Sir John Gielgud, Alan Bates and Denholm Elliott.
Celia played Kate MacLeod in the 1986 Christopher Lambert film Highlander.
In 1994, Celia played Mrs. Moritz in Kenneth Branagh's film adaptation of Mary Shelley's gothic novel Frankenstein.
In 2005, Celia appeared in Emma Thompson's film Nanny McPhee as Selma Quickly.
She makes an uncredited appearance as a maid in the 1978 Sir Peter Ustinov film Death On The Nile.
Celia appeared in two episodes of the cult BBC drama about the class divide Upstairs, Downstairs in 1974.
In 2003, Celia starred in the one woman play Unsuspecting Susan, playing gossiping housewife Susan Chester.
She has been a member of the Citizen's Theatre Company in Glasgow.
In 2001, Celia played Aunt Sadie in the BBC adaptation of Nancy Mitford's novel Love In A Cold Climate.
Celia has toured with the Royal Shakespeare Company as an understudy.
Her first stage performance was in the pantomime Dick Wittington. She played a rat.
Celia attended the Guilford School of Acting. While she was there, she trained to teach dance to children.
Initially Celia wanted to be a dancer however she went into acting after being rejected from dance school.
When she was young Celia had a nanny, her name was Thelma Baker.
Her Scottish father was a radiologist.
Celia has one son with actor Benjamin Whitrow.
She is the fourth of five children.
Celia played gravy obsessed Una Alconbury in both Bridget Jones movies starring Renee Zelwegger.
She is also a successful stage actress and has starred in Sam Mendes' Hebeas Corpus at the Donmar Warehouse.
Celia played cat obsessed aristocrat Lady Gertrude Groan in the lavish BBC drama Gormanghast.
Celia has appeared numerous times as competitive public relations officer Claudia Bing in the award winning sitcom Absolutely Fabulous.
In 1990, Celia played Miss Jewsbury in the award winning BBC production Oranges Are Not The Only Fruit, an adaptation of Jeannete Winterson's novel.
She appeared in the second series of the cult Jersey detective series Bergerac as Marianne Bellshade.
Celia auditioned for the role of Darth Vader's mother. She did not get the part but she can be seen playing Fighter Pilot Bravo Five in 'Stars wars Episode 1: The Phantom Menace.