It's always nice when fandoms collide and that's just about to happen when Game of Thrones meets Doctor Who.

That's right, Maisie Williams, who plays Arya Stark on the hit HBO drama, will be stepping inside the TARDIS for an adventure in time and space, as she takes on a guest starring role on the BBC's hit sci-fi television series, Doctor Who.

"I'm so excited to be working on Doctor Who as it's such a big and important part of British Culture," says Williams on her first day on the Doctor Who set. "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."

So who will be Williams portraying on Doctor Who? Not a lot about her character is known, although series showrunner Steven Moffat says she will challenge the Doctor. Of course, Game of Thrones fans might imagine Arya Stark herself in the TARDIS, as that sounds about right, perhaps threatening the Doctor with the pointy end of Needle.

"We're thrilled to have Maisie Williams joining us on Doctor Who,"' says Moffat. "It's not possible to say too much about who or what she's playing, but 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."

Production of season nine of Doctor Who is well underway, and we've already learned that another actress, Michelle Rodriguez, will be reprising her role as Missy, the female version of the Master this season. Missy supposedly died last season, but as she really just disappeared, fans were sure the character would return.

The new season of Doctor Who will also feature other guest stars, including Rufus Hound, Tom Stourton, Ariyon Bakare, Simon Lipkin and Barnaby Kay. New episodes should start airing later this fall.

Meanwhile, Game of Thrones fans can catch Williams on HBO when the series fifth season premieres on April 17.

Williams has also been rumored as the lead in the movie adaptation of video game The Last Of Us. She also starred in the docu-drama Cyberbully, as well as portrayed one of the leads in The Falling. Williams has received three Screen Actors Guild Awards nominations and was recently given a Shooting Star Award at the Berlin Film Festival.

[Photo Credit: BBC]

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