Briers attended St Paul's Girls' School, London (1978—85); Lancaster University (where she studied theatre and sculpture); and then a three-year acting course at the Bristol Old Vic Theatre School and National Youth Theatre As well as acting, Briers plays both the piano and flute.
Briers is best known for playing Mary Bennet in the BBC's television adaptation of Pride & Prejudice (1995). Coincidentally, she appeared in an episode of Game On with Pride and Prejudice cast member Crispin Bonham-Carter, with Victoria Hamilton (Pride's Mrs Forster) in a stage production of As You Like It, and with Tom Hollander (Mr Collins in the 2005 version) in a stage production of Don Juan.
On TV, Briers narrated the documentary The Riddle of Pompeii, the 2001 series Nurses and Ladette to Lady.
In 2007 she appeared in Some Kind of Bliss, a new one-woman play by Samuel Adamson at the Trafalgar Studios, a role she reprised in the 2008 Brits off Broadway season.
In 2008 she appeared in the BBC drama Einstein and Eddington and a West End revival of Chekhov's Ivanov. In 2011 she appeared in BBC Four's Twenty Twelve as Anna Mitchell, one of the three candidates for the post of curator of the Cultural Olympiad.
