Greig Watson Entertainment reporter, BBC News

Portman says she based her performance on flamenco dancers

In her new film, Goya's Ghosts, she plays the victim of the infamous Inquisition, resurgent in late 18th-Century Spain.

She is hung up by her arms to secure a confession that her character is a heretic.

The image recalls another of her roles, Evey Hammond in V for Vendetta, where an interrogation scene meant her head was shaved.

I don't want to be the cheap torture girl for the rest of my career Natalie Portman

So is she deliberately choosing tough scripts?

"No, no," she says. "I'm not consciously going for those roles.

"On V, I was really into the whole story but on this I was wondering whether it was too much. But what could I do? I wasn't going to turn down such great roles.

"Hopefully I won't be typecast. I don't want to be the cheap torture girl for the rest of my career."

Portman first made headlines aged 12 as the gun-toting Matilda in Luc Besson's thriller Leon.

As her acting career took off she surprised many by walking away from the cameras to study psychology at Harvard.

But it did not stop her securing a permanent place in popular culture as Queen Amidala in the Star Wars prequels.

She then won an Oscar nomination in 2004 for her portrayal of a stripper in Closer.

Goya's Ghosts, directed by Oscar-winner Milos Forman, sees her play Ines, the daughter of a Spanish merchant.

Portman plays a mother and daughter in the film

Her beauty leads to her becoming the muse of the painter Goya - but also to her being thrown into jail, only to re-emerge years later as a tortured, broken soul.

She also portrays Ines's daughter, Alicia, who grows up unaware of her mother's ordeal or even her true parentage.

The 25-year-old says she relished the opportunity of such a complex set of characters.

"It was definitely exciting to get the opportunity to play what was effectively three different characters in the same movie," she says.

"I knew that was going to be really difficult but working with Milos Forman was such a great opportunity that I was not going to pass up."

Self-critical

So how did she define these people who all, obviously, had the same face?

"With Ines it is almost crucial that she is ordinary. She should just be a pretty face, because she is not supposed to be a stand out. The point is that this could happen to anyone and she is unformed, she is a child.

"The person who comes out of the prison has had all these terrible experiences forced onto her and only has one concern, her child.

Director Forman has won two Oscars

"With Alicia I was really inspired by the flamenco dancers in Spain. They were just so sexy, fiery and strong.

"They have so much personality. There was one that I saw at a flamenco performance and I just tried to channel her."

Portman says she knew next to nothing about the tempestuous period in which the film was set or about Goya, played by Swedish actor Stellan Skarsgard, around whom the film revolves.

"The only thing I knew about the Spanish Inquisition was probably from the Monty Python sketch or History of the World," she says.

"I knew Goya's paintings very vaguely - I'd been to the Prado gallery once before but, luckily, because we did all the pre-production work in Madrid, I got to go there every day for a month. There was an art historian that took me around and explained everything to me - it was really quite amazing."

Portman's passion for acting comes through in her conversation but falters when discussing what she thinks of the results.

"I don't watch myself in general. I will see it once when the movie comes out but I can't after that because I will start hating myself. I am so not objective about myself, I always hate myself!"