Maisie Williams, who rose to considerable fame for portraying Arya Stark in HBO’s widely acclaimed hit series ‘Game of Thrones,’ will be making a guest appearance in ‘Doctor Who.’

The 17-year-old actress already began filming for a guest role in the next episodes of BBC’s sci-fi show specifically the second one in which Peter Capaldi will take on the role of the Doctor.

Two upcoming period adventures are set, titled ‘The Girl Who Died’ by Jamie Mathieson and Steven Moffat, and ‘The Woman Who Lived’ by Catherine Tregenna.

‘Doctor Who’ showrunner Steven Moffatt already expressed his anticipation in working with Williams, although he preferred not to reveal details about which character the actress will be portraying. One thing is for sure though - Williams’ role will be to “challenge the Doctor in very unexpected ways.”

Taking a break from the medieval fantasy epic, the Bristol-born actress recently spent some time in Cardiff to take on her part for the ‘Doctor Who’ series to be aired on TV this year.

“I’m so excited to be working on Doctor Who as it’s such a big and important part of British culture,” Williams said.

The actress also shared her excitement about meeting new cast and crew members, and the fact that the filming takes place near her hometown.

Another cast member confirmed to make an appearance in ‘Doctor Who’ this year is British actor and comedian Rufus Hound, who calls himself a “massive” fan of the sci-fi series.

Aside from having a key role in ‘Game of Thrones’, which is based on George R.R. Martin’s novel series ‘A Song of Ice and Fire,’ Williams also made an appearance on the Channel 4 docu-drama, ‘Cyberbully,’ in which she also played the main character. Exchanging drama for music, the actress also appeared in the official music video for ‘Oceans’ by Seafret.

This April, Williams returns to her most famous role to date as ‘Game of Thrones’ makes its comeback for its fifth season on HBO. The stars of the series came to London last month for the world premiere of Season Five.

Kit Harington, Gwendoline Christie, Sophie Turner, and Alfie Allen were all present to attend the launching of the upcoming season at the Tower of London, two months prior to the show’s debut on Sky Atlantic this April.

In addition, Williams will star alongside Maxine Peake in the upcoming drama film, ‘The Falling,’ helmed by Carol Morley.