Game of Thrones, Maisie Williams

Living in the fantasy world of HBO's Game of Thrones can be brutal, especially on the children.

Just ask newcomer Maisie Williams who plays 11-year-old Arya Stark. It's not easy being a Stark family member these days. In the season premiere, Arya's younger brother Bran (Isaac Hempstead-Wright) witnessed his first beheading and later took a crippling tumble out of a tower window.

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In Sunday's episode (airing 9/8c), Arya must run for her life after her father Ned Stark (Sean Bean) has been betrayed and captured in a bloody coup at King's Landing. Add graphic nudity and sex scenes to the mix, and it's clear that Game of Thrones is not meant to be kid-friendly viewing.

"Mom lets me watch all of it," Williams, 13, admits to TVGuide.com. "I usually cover my eyes for some parts because it's a bit embarrassing, but it's just acting at the end of the day. And I've seen how the beheading was done and things like that. It looks scary, but I know in real life it was not bad."

Despite being exposed to the rather adult situations, Williams remains refreshingly unjaded and identifies with her spirited character.

"I describe Arya as quite feisty, a tomboy," she says. "She likes to break the rules and doesn't really like being how everyone thinks she should be. I like playing outside and messing around. When I was in primary school my best friend was a boy and we always goofed around, climbed trees, got holes in my trousers and muddied all my tops and things like that, a complete nightmare for the washing, but great fun. I would always put a bit of Maisie into everything."

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Arya's biggest antagonist is her much more feminine and refined older sister, Sansa, played by Williams' real-life friend Sophie Turner. Sansa is blindly devoted to the spoiled and corrupt Prince Joffrey (Jack Gleeson) and even lied to protect him once.

"Arya thinks of Sansa as a bit iffy, sort of clueless as to what's going on around her," Williams explains. "She finds Sansa annoying as she's always going on about princes and marrying and having children and Arya just thinks all that's way, way in the future. It's a waste of time. Joffrey is not very nice and she can see that, but Sansa can't. Arya is definitely trying to get through to people what she knows, but sometimes it's not always the best way and she gets into trouble."

Trouble finds Arya, however, when the Lannister guards who had seized her father are now after her. Luckily, Braavosi fencing master Syrio Forel (Miltos Yerolemou), had taught her the rudiments of defending herself and runs interference for her. Williams never performed any kind of swordwork professionally and looked forward to learning the new skill for Game of Thrones.

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"I picked it up pretty quickly," she says. "I thought it would be like learning a dance routine. It's like one move after another and you know the order it comes. You work together because you can't just throw the sword any old place. You've got to do it in certain places so the reaction can come at the same time. Otherwise, it looks really fake."

And although Williams doesn't claim to be the best swordfighter, she at least tried to keep one aspect of Arya faithful to the character in George R.R. Martin's A Song of Ice and Fire novels on which Game of Thrones is based.

"I'm right-handed, and when Mom was reading the first book, she told me about Arya being left-handed," she says. "From then on, I was like, 'Alright, I'm going to try to do everything left-handed.' When I was practicing out in the garden and things I would do left-handed just to feel that rhythm. Unfortunately, when it came to filming, sometimes I have to do things right-handed because of the camera angle and things like that. So some people are a bit annoyed that Arya hasn't done everything left-handed. I wanted to. I really did. But sometimes it was just too tricky and we couldn't do it."

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She consoles herself by noting that a Braavosi "water dancer" would probably be ambidextrous. "I'm sure Syrio would teach Arya to use both hands as well," she says.

Game of Thrones has already been picked up for a second season, but until she returns to work sometime this summer, Williams is happy to stay far away from the Belfast, Ireland set.

"The main thing that I'm definitely not going to miss is when we were in Belfast," she says. "The toilets that they had were full of spiders and I cannot stand spiders. They're the scariest thing on this planet. It was just horrible. I dreaded going to the toilet over there."

Game of Thrones airs Sundays at 9/8c on HBO.

Here's a sneak peek of Sunday's episode, "The Pointy End":