The Other Boleyn Girl (12A) Drama about two sisters vying for the attention of King Henry VIII, starring Scarlett Johansson.

BASED on the best-selling novel by Philippa Gregory, The Other Boleyn Girl is a tale of intrigue, romance, and betrayal set against the backdrop of a defining moment in history.

Two sisters, Anne and Mary Boleyn, are driven by their ambitious father and uncle to advance the family's power and status by courting the affections of the king of England (Eric Bana).

Leaving behind the simplicity of country life, the girls are thrust into the dangerous and thrilling world of court life - and what began as a bid to help their family develops into a ruthless rivalry between Anne and Mary for the love of the king. Initially, Mary wins King Henry's favour and becomes his mistress, bearing him an illegitimate child.

But Anne, clever, conniving, and fearless, edges aside both her sister and Henry's wife, Queen Katherine of Aragon, in her relentless pursuit of the king. Despite Mary's genuine feelings for Henry, her sister Anne has her sights set on the ultimate prize; Anne will not stop until she is Queen of England.

As the Boleyn girls battle for the love of a king - one driven by ambition, the other by true affection - England is torn apart. Despite the dramatic conse-quences, the Boleyn girls ultimately find strength and loyalty in each other, and they remain forever connected by their bond as sisters.

For director Justin Chadwick, the central relationship is not necessarily the famous one between Henry and Anne but the one between Anne and her sister, Mary, who vied with her for the king's attention. "Anne and Mary do some terrible things to each other, there's rivalry and jealousy between them, but ultimately, they're sisters," he says.

Natalie Portman takes on the role of Anne Boleyn, who would replace her sister as the king's mistress, becoming his queen. "It's easy to see the story for its place in history, but at its heart it is a family story, a story between sisters," says the actress.

Scarlett Johansson plays the "other" Boleyn girl, Mary, who would happily fade into history. "Sibling relationships are complicated," she says. "Everyone can understand that jealousy and competition. The bond is very strong; only your siblings can read you so well and know instinctively how you feel."

"Whichever sister becomes the more successful in their rivalry for the king's affections, the other one becomes the other' Boleyn," says Portman. "Anne totally buys into the whole competition, while Mary chooses a way to be happy without life in the court, and she ultimately wins by allowing Anne to have the victory that destroys her. It's a family story, with love and intrigue, about children who are corrupted by a world which pushes them to compete rather than support each other. Mary, the survivor, is the one who rejects that world."

Joining Portman and Johansson are Eric Bana as King Henry VIII, Kristin Scott Thomas as Lady Elizabeth, and David Morrissey as the Duke of Norfolk.

"The Boleyn girls are written as two halves of the same person. I think that is always true of sisters of a similar age, even if they don't always want to admit it," says Johansson. "What Mary admires and is repulsed by in Anne are traits that she wishes she had herself. Similarly, Anne comes to realise at the end of the story that she wishes she had some of Mary's traits."

"My wife had read the book, as had many women I know, as I later discovered," says Bana, who plays the young king. "I think women are so attracted to it because it shows two very strong sides of the female psyche: in modern terms, Anne is the professional, ambitious woman, while Mary wants love and family.

"What appealed to me was the complexity of the man," he continues. "I felt that even when he behaved badly, there was logic to it that I could understand. By the end of the film we can see where he is heading - he's becoming a spoiled brat, unpredictable and dangerous. In a sense, he's leading a double life - he's one man in full view of the court, but behind closed doors, he is mesmerised by Anne."