She won a Laurence Olivier Award for Best Actress in 2007 for Much Ado About Nothing, and was nominated in 2011 and 2015 for her roles in The Little Dog Laughed and Women on the Verge of a Nervous Breakdown.

Her father, Eric (1906–1998), worked as a colour chemist creating dyes, and her mother, Ann (1933–2001), was enthusiastic about amateur dramatics.

Fran was a friend of the main character, Bernard, and originally owned a gift shop called "Nifty Gifty" next door to his bookshop.

[14] In 2004, she played constantly embarrassed surgical registrar Dr Caroline Todd, the lead character in the Channel 4 comedy drama series Green Wing.

She starred in the BBC comedy drama series Love Soup (2005), as Alice Chenery, a lovelorn woman working on a department store perfume counter, in a role specifically written for her by David Renwick, whom she met in 2003 when she appeared in an episode of Jonathan Creek.

Greig also stars in the Channel 4 sitcom, Friday Night Dinner, as Jackie Goodman, the mother of a North London Jewish family.

She is also the lead in The Guilty in the three-part series on ITV in 2013, playing DCI Maggie Brand who investigates the death of a young child who went missing five years previously.

During 2006 and early 2007, Greig played Beatrice in a much acclaimed production of Much Ado About Nothing for which she won a Laurence Olivier Award,[22] and Constance in King John, as part of the Royal Shakespeare Company's The Complete Works season.

Whilst the win itself was a surprise,[23] her acceptance speech was received very well as being highly entertaining,[24] claiming that she was so excited that she had wet her dress.

[32] Greig starred in The Little Dog Laughed by Douglas Carter Beane at the Garrick Theatre in London, which ran a limited season until 10 April 2010.

[34] In October 2011 she was Hilary, the central character, in Jumpy at the Royal Court, London.,[35] which later transferred to the Duke of York's Theatre in the West End.

In October 2016, she returned to the Hampstead Theatre to play Empty in The Intelligent Homosexual's Guide to Capitalism and Socialism with a Key to the Scriptures by Tony Kushner.

[39] Since 1997 she has been married to actor Richard Leaf, whom she met at a wrap party of Neil Gaiman's 1996 miniseries Neverwhere,[5] and has three children.

[40][41] She is a supporter of the National Health Service, giving her backing to a rally organised by pro-NHS protest group NHS Together.