Game of Thrones' Maisie Williams joins Doctor Who
Game of Thrones star Maisie Williams is in the new series of Doctor Who.
The BBC hasn't announced which part she'll play, but lead writer Steven Moffat says: "She is going to challenge the Doctor in very unexpected ways.
"This time he might just be out of his depth, and we know Maisie is going to give him exactly the right sort of hell."
She says she's looking forward to filming the show as "it's such a big and important part of British culture".
"I can't wait to meet the cast and crew and start filming, especially as we'll be shooting not too far from my home town."
Bristol-born Maisie has played Arya Stark in the fantasy drama Game of Thrones since 2011.
Arya is a young girl from a noble family, who brandishes a sword and is often mistaken for a boy.
She's only 17, but she's a three-time Screen Actors Guild Awards nominee. In February she was given a Shooting Star Award at the Berlin Film Festival.
She won the 2013 BBC Radio 1 Teen Award for best British actor.
Maisie has starred in the one-off docu-drama Cyberbully and was one of the leads of Carol Morley's BBC One drama The Falling.
Series nine of the relaunched Doctor Who returns to BBC One this autumn.
Two period adventures are being filmed - The Girl Who Died written by Jamie Mathieson and Steven Moffat and The Woman Who Lived by Catherine Tregenna.
Comedian and actor Rufus Hound - who recently appeared in the Channel 4 series Cucumber - also joins the guest cast, alongside BBC Three's Siblings and CBBC's Horrible Histories star Tom Stourton.
Doctor Who is one of BBC One's most highly-regarded dramas, with series eight averaging 7.4 million viewers in the UK across 12 episodes.