The Other Boleyn Girl is a missing chapter in Henry VIII's sex life, and one of the most ravishing pieces of trash I've seen, writes James Christopher. The Tudor costumes are fabulous. The cast are skin-cream gorgeous. And the bitchy fight between the two Boleyn sisters over who performs better in bed with the hunky King of England is X-rated Mills & Boon. Women will adore the sibling scrap between Natalie Portman's greedy Anne (the calculating tease who marries Henry) and Scarlett Johansson's tender-hearted younger sister, Mary.

But I'm bemused as to why this profoundly unstable monarch has become such a heroic box office draw. A chick-flick romance featuring Henry VIII is surely an insane contradiction in terms considering his axe-happy way with wives and the 80,000 people who went to the gallows during his regal watch.

Justin Chadwick's film has no time for such irritating details. His ugly story unfolds like a glamorous Fleet Street scandal. The randy Henry (Eric Bana), is bored to tears by his saintly Spanish wife, Catherine of Aragon. Bana's King is a brooding loner with huge, furry, Holbein shoulder pads and a George Michael beard. He wants fresh young meat between the bear-rug sheets, and there isn't a noble in his scheming court who wouldn't pimp his own daughter for the royal privilege. David Morrissey is terrific as the wicked, power-hungry uncle who places both the Boleyn sisters under Henry's nose. His sneering voice is one of the few pleasures of the film.

Johansson's shy country girl, Mary, is the King's first conquest despite having recently married a spotty merchant. The actress pouts and blinks like a Dorset milkmaid. Her wildly jealous and sophisticated sister, Anne, eventually knifes her way into the King's favour, but is fatally blamed - in the space of ten minutes - for the Reformation, the war against France and failing to produce a son. Bana turns into a psychopath for the sole purpose of hustling the plot to a sharp conclusion.

Chadwick's melodrama hinges on the poisonous bond between Johansson and Portman as love rivals and sisters. Ultimately we are meant to eat chocolates, admire their trembling lower lips, and choose sides.

12A, 115mins

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