Reality begins to crumble for Natalie Portman's Nina, as she struggles to cope with the pressure of landing the lead role in Swan Lake.

While she's at home playing the virginal white swan, the role also calls for her to portray the seductive black swan.

Under pressure from her manipulative company director, her clingy mother and her own fear of failing, Nina becomes increasingly desperate. Things aren't helped by the recent arrival of a new dancer in the company, the wild Lily, played by Mila Kunis, who seems to be all the things Nina's not.

The viewer experiences Nina's world collapsing along with her. It's expertly told by Darren Aronofsky, and set, of course, to Tchaikovsky's wonderful music.

Some reviews have hailed Black Swan for its originality and intensity. It perhaps won't seem so novel to fans of Asian horror, as it has a lot in common with films like Audition or A Tale of Two Sisters. But that's intended as a compliment.