Knightley lined up to play Scott Fitzgerald's Zelda in biopic

Zelda Sayre was one of the most controversial literary figures of her time. Some claim that her marriage to F Scott Fitzgerald inspired him to produce the Jazz Age's best novels. Others say she stifled his creativity.

The debate will be sparked again, as their troubled relationship is examined in a new biopic, The Beautiful and the Damned. Keira Knightley is said to be in negotiations to play the lead.

Zelda was a leading light of the roaring Twenties, and Fitzgerald was the era's most brilliant writer. When the two married in 1920, they were seen as the perfect society couple. But their marriage was far from ordinary – thanks, in part, to Zelda's outrageous behaviour and schizophrenia. Some literary experts suggest that it was her influence that led Fitzgerald into spiralling fits of jealously and alcoholism.

But Cathia Jenainati, associate professor of English writing at Warwick University, said: "It was Ernest Hemingway, who was friends with Fitzgerald, who started this myth that Fitzgerald's loss of social control resulted from Zelda's influence over him... But I think it is too simplistic to draw a connection between male genius and female influence. His writing did suffer but I'm not sure it was because of her influence."

The film is written by Hanna Weg, who also wrote Enigma, and directed by Nick Cassavetes. It is to begin shooting in April, although the role of Fitzgerald has not yet been cast.

The film's title is taken from Fitzgerald's second novel, which tells the story of Anthony Patch, an alcoholic socialite, and his wife Gloria. On its publication in 1922 it was hailed as a searing portrait of the eastern American elite of the Jazz Age.

Zelda grew up in a wealthy Southern family. Soon after finishing high school, she met Fitzgerald at a dance, and although he is said to have professed his infatuation, she continued seeing other men. After marrying, they spent the early part of the 1920s as literary celebrities in New York.

The strain of their union allegedly led Scott to increased alcoholism, with some noting that he never regained the critical acclaim he received for his celebrated third novel, The Great Gatsby, published in 1925. It also inflamed Zelda's mental instability, leading to her admittance to a sanatorium in 1930.

Feminists, however, have championed Zelda as a woman who stood up to an emotionally abusive partner.

While in a clinic in Maryland, Zelda wrote the novel Save me the Waltz. Fitzgerald was incensed that she had used some real-life material from their marriage even though he did the same for Tender Is The Night, in 1934. Both books presented contrasting yet insightful portrayals of their troubled marriage.