Based on Amanda Foreman’s biography of Georgiana, Duchess of Devonshire, The Duchess is a BBC-financed costume drama, tailor-made for modern tastes. For, along with its multistorey wigs, petticoats and grand palaces, we get a “beautiful” fashion icon and celebrity heroine with a broken heart.

The film’s star, Keira Knightley, has criticised attempts to market the film as a version of the Princess Diana story, but the parallels are just too striking to be ignored: a beautiful member of the Spencer family marries an older man who is cold and uncaring. He takes a mistress, she becomes a fashion icon who captivates every heart in the land - except her husband’s - and, eventually, takes a lover. Who is Keira kidding? Only herself.

The Duchess doesn’t want to be seen to be cashing in on the Diana story, so it presents itself as a serious, neo-feminist tale of a smart, beautiful and independent-minded woman who bravely faces the cruel emotional inequities of aristocratic privilege and cultural patriarchy. Beneath its pretty facade and artistic pretensions, however, it offers the pleasures of the Diana story - that bittersweet mix of triumph and tragedy - for people who look down on the princess and her fans.

The film starts with the marriage of the high-spirited 17-year-old Georgiana (Knightley) to the Duke of Devonshire (Ralph Fiennes) in 1774. It’s a match made in heaven and lived in hell. She expects a loving husband; he expects an accomplished breeder to provide a male heir. At one point, Georgiana complains to her mother (wonderfully played by Charlotte Rampling) that her husband gives more affection to his dogs than to her. Her unsupportive mother tells her she must do her duty; the duke does the dirty on his wife with another woman.

Still, Georgiana becomes a famous beauty and fashion icon. All of London society - and the British public at large - is dazzled by her. It is impossible to hear the line “He must be the only man in England who doesn’t love his wife” and not think of you-know-who. Buried alive in a loveless marriage, Georgiana turns for solace to her new best friend, Lady Bess Foster (Hayley Atwell), but Bess becomes her husband’s mistress. Eventually, they live in a ménage à trois, and Georgina has an affair with the handsome politician Charles Grey (Dominic Cooper).

The Duchess is a simplistic melodrama of wicked men and wronged women. Foreman has written that Georgiana would never have liked to see herself as a victim, but this is exactly what the film makes her out to be. Which is a shame, because the duchess we meet in Foreman’s biography is far more complex and interesting than the one we see on the screen. The film makes passing references to her political campaigns on behalf of the Whig party, but such scenes illustrate only the power of her celebrity, not the passion of her convictions. As for her celebrated intelligence and wit, the film has about as much interest in Georgiana’s mind as her indifferent husband does. Instead, it celebrates Georgiana as a society figure and fashion icon, without showing - as Foreman does - the emptiness of such triumphs or her boredom with the beau monde.

More importantly, the film concentrates exclusively on the demon figure of Georgiana’s horrible husband, instead of showing her own inner demons and their destructive role in her life. The Duchess of Devonshire was addicted to gambling, took drugs and binged and purged like a bulimic. Likewise, the real story of Lady Bess Foster is more interesting than the one we see. The film shows her as a good friend to Georgiana, one who reluctantly becomes the duke’s mistress so she can see her children from her unhappy marriage. Foster’s love for Georgiana was actually more like that of a celebrity stalker; she wanted everything the duchess had, including her husband.

Even within its own limited terms, the film doesn’t work. It lacks not only the visual sumptuousness you’d expect from such a costume drama, but emotional punch. There’s something cold about Knightley’s screen presence, and she never conveys the anger and heartbreak of her character. At one point, the desperate duchess asks her cheating husband: “What’s wrong with me?” It should be a killer line, but Knightley can’t hit the right note of pathos. Thank heavens for Ralph Fiennes. He has taken a one-dimensional character and made him into a gripping study of an emotional cripple: half man, half monster.

If only the film had more ambition and bite. By the end, we’re left with little to think about, other than, wasn’t it all terribly sad, and weren’t men monsters back then! Still, if you want suffering posh people in pretty frocks, The Duchess won’t disappoint.

d. Saul Dibb
12A, 110 mins

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