Keira Knightley and Elisabeth Moss in The Children's Hour, directed by Ian Rickson West End early 2011

Keira Knightley and Elisabeth Moss have been cast in Lillian Hellman's The Children's Hour, which is due to open in the West End early 2011.

Venue, full casting, production information and performance schedule will be announced shortly.

It is directed by Ian Rickson, and produced by Sonia Friedman Productions & Scott Landis.

When a troubled teenager starts to spin a web of deceit, all around her are soon caught up in it. Karen Wright (Keira Knightley) and Martha Dobie (Elisabeth Moss) have worked for years to establish their all-girls boarding school, and now, with the school flourishing and Karen on the verge of marriage, their lives and loves finally appear secure. However, when malicious student Mary runs away from the school and seeks to avoid being sent back, she draws on hearsay, gossip, and her own imagination, to concoct a story that threatens the school, the marriage, and their entire futures.

Keira Knightley was last on stage in The Misanthrope directed by Thea Sharrock at the Comedy Theatre. Her many film credits include Never Let Me Go which opened the 2010 London Film Festival, Bend It Like Beckham, Love Actually, Pirates of the Caribbean trilogy, King Arthur, The Jacket, Pride and Prejudice, Domino, Silk, Atonement, The Edge of Love , The Duchess, Last Night, and the forthcoming London Boulevard and A Dangerous Method. Her television credits include the critically acclaimed remake of Doctor Zhivago, Oliver and Coming Home.

Elisabeth Moss, who will make her West End debut in The Children's Hour, is best known for playing the role of Peggy Olson in the ongoing award-winning television series Mad Men, for which she has received both Emmy Award and SAG Award nominations, as well as for the role of Zoe Bartlett in The West Wing. Moss made her Broadway stage debut in David Mamet's Speed the Plow in 2008. Her film credits include Get Him to the Greek, Did you Hear About the Morgans? and Girl, Interrupted, as well as the forthcoming On the Road and Darling Companion.