Rachel Weisz didn't know the back story to 'Agora'.

The British actress plays the lead character Hypatia in the film and admits the true-life tale of the female philosophy professor in 4th Century Egypt was not she was familiar with.

She said: "The thing I couldn't believe is that this is a true story. Everything that happens in the film is true - apart from her having the slave and the slave being in love with her, that's a little Hollywood invention - but the fact that no has made a film about her is pretty extraordinary.

"I'd never heard of her even. And she's a remarkable, remarkable woman."

The 40-year-old star also thinks many people still continue to prejudice her for not being the kind of woman who wanted to settle down and have children.

She told BBC News: "I think no would look at Leonardo Da Vinci and say, 'Oh isn't it sad that he didn't have kids or a wife' Everyone understands that he is busy. But when it comes to a woman - and I was the same I thought, 'Ah, wouldn't it be nice if she could be a mum and have a partner and get married' - but I realised if it was man no one would really think that."

'Agora' is being released country by country throughout 2010.