Early life

Walker was born in Warrington, Lancashire, England. She attended Padgate Church of England Primary School in Warrington and Silverdale Preparatory School, West Acton, London. At 16, Walker graduated from Ballet Rambert School in Twickenham and began her career as a dancer but had to abandon dancing after a leg injury at the age of 18. She then decided to become an actress. She moved from the Drama Centre in London to the Royal Shakespeare Company, where she played bit parts for six months before graduating to small roles on television.

Film and television roles

Walker landed the title role in the television series Lorna Doone before making her feature debut in Shogun Mayeda (1991). In that same year she appeared in Les Equilibristes and in Mike Newell's Enchanted April, in which she played an aristocrat eager to escape the attentions of her persistent male admirers. Walker first garnered international attention in 1992 as a single-minded English member of an Irish terrorist group in Phillip Noyce's Patriot Games. In 2003 she had a starring role in the BBC drama series State of Play.

Between 2005 and 2007, Walker played Atia of the Julii in both seasons of the HBO/BBC2 television series Rome. Her performance earned her a Golden Globe nomination in 2005 for Best Performance by an Actress In A Television Series - Drama. She next played the sinister Catherine Braithwaite in Deus Ex Machina, a two-episode story of the BBC television "cold case" crime series Waking the Dead, which also aired in January 2007. In May 2007, Walker appeared as Lady Bess Sedgwick in ITV's Marple: At Bertram's Hotel, and then played sugar heiress Ellis Samuels in the CBS television drama Cane, which premiered 25 September 2007.

In May 2008, Walker was cast as Sister Clarice Willow, headmistress of a private religious school, in Syfy's Battlestar Galactica prequel series Caprica. In 2011 she guest starred as Ranna Seneschal, leader of the underground city of Praxis, on Sanctuary.

In 2012, she starred in BBC's crime drama Prisoners Wives as crime wife Francesca Miller. She returned to the role in 2013 for the second series.

In 2014, she had a recurring role as the character Delphine Day in the ITV series Mr Selfridge.

In 2015, she appears in The Syndicate - series 3 as DI Baker.

Personal life

She is one of four siblings. Walker has two children from two previous relationships, Giorgio (b. 1993) and Delilah (b. 2000). She currently lives in the United States. On 23 October 2008, Walker married former actor Laurence Penry-Jones (brother of Rupert Penry-Jones), most famous for his role as Dr. Oliver Berg in the BBC soap Doctors.

Filmography

Film

Year	Title	Role	Notes
1990	Lorna Doone	Lorna Doone	Television film
1991	Journey of Honour	Cecilia
1991	Ao Fim da Noite
1992	A Dangerous Man: Lawrence After Arabia	Mme. Dumont	Television film
1992	Secret World of Spying, TheThe Secret World of Spying	Annette	Television film
1992	Walking a Tightrope	Hélène Lagache
1992	Enchanted April	Caroline Dester
1992	Patriot Games	Annette
1993	Trial, TheThe Trial	Leni
1993	Sliver	Vida Warren
1995	Restoration	Celia Clemence
1996	Emma	Jane Fairfax
1997	Roseanna's Grave	Cecilia
1997	Robinson Crusoe	Mary McGregor
1997	Gambler, TheThe Gambler	Polina
1997	Woodlanders, TheThe Woodlanders	Mrs. Charmond	Television film
1997	Bandyta	Mara
1998	Curtain Call	Julia
1998	Talk of Angels	Mary Lavelle
1998	Dark Harbor	Alexis Chandler Weinberg
1999	½ Women, 88 ½ Women	Palmira
2000	After Alice	Dr. Vera Swann
2002	D-Tox	Jenny
2002	Savage Messiah	Paula Jackson	Nominated—Genie Award for Best Performance by an Actress in a Leading Role
2002	Jeffrey Archer: The Truth	Mrs. Archer	Television film
2004	Control	Barbara Copeland
2006	Scenes of a Sexual Nature	Esther
2010	Clash of the Titans	Cassiopeia
2012	John Carter	Sarkoja

Television

Year	Title	Role	Notes
1989	Storyboard	Margaret Niner	Episode: "Hunted Down"
1989	Rules of Engagement	Fiona	2 episodes
1990	Agatha Christie's Poirot	Nick Buckley	Episode: "Peril at End House"
1990	Screen Two	Nadja	Episode: "The Kremlin, Farewell"
2003	Mayor of Casterbridge, TheThe Mayor of Casterbridge	Lucetta Templeman	Television series
2003	State of Play	Anne Collins	6 episodes
2005-2007	Rome	Atia of the Julii	22 episodes Nominated—Golden Globe Award for Best Actress - Television Series Drama Nominated—Satellite Award for Best Supporting Actress - Series, Miniseries or Television Film
2007	Waking the Dead	Catherine Braithwaite	2 episodes
2007	Agatha Christie's Marple	Bess Sedgwick
2007	Cane	Ellis Samuels	13 episodes
2009	Numb3rs	Dr. Lorna Ludlow	Episode: "Animal Rites"
2009-10	Caprica	Clarice Willow	17 episodes
2010	Sanctuary	Ranna Seneschal	2 episodes
2012-13	Prisoners’ Wives	Francesca	10 episodes
2012	The Mentalist	FBI Agent Alexa Shultz	2 episodes
2013	Warehouse 13	Charlotte Dupres	4 episodes
2014	Mr Selfridge	Delphine Day	4 episodes
2015	The Syndicate	DI Baker	6 episodes
2016	Line Of Duty	Gill	6 episodes

[ Source: Wikipedia ]