Even styled in the manner of Posh Spice circa that terrible collaboration with Dane Bowers, you would have to be “out of your mind” to suggest that Scarlett Johansson was not inherently pretty. Nevertheless, here she is at the premiere of her new film, He's Just Not That Into You (not with hair like that he isn't, dearie), looking disturbingly reminiscent of Posh in her Essex phase.

Everyone knows that Mrs Beckham is steadily gaining influence among the stars of Tinseltown, but we must hope that Johansson's ironed-out hair and spidery eyelashes are not indicative of a wider Posh-inspired trend.

Who knows what Johansson's stylist was thinking when he or she advised the poor girl to dye her hair the colour of beetroot and then stick it tightly to her face with spit? It's just bonkers. Johansson is a Jessica Rabbit sort of a star, all soft curves and lovely, round features - so giving her a harsh, semi-dominatrix hairdo is a disaster. Ditto the eye make-up. The heavy black eyeliner and over-extended eyelashes bring an artificial edge to her extreme prettiness.

It's an unwelcome departure from the soft, strawberry blonde starlet we know and envy. The hairdresser Luke Hersheson agrees. “She may well have had to dye her hair for a part in a film,” he says. “However, what I find bizarre is the late-Nineties flat, ironed hair which is the most unflattering look on her. Scarlett is a glamorous movie star, so why the change?”

Hersheson's advice is to go back to being a blonde. She could start by restoring some of the lost volume: Aveda's Pure Abundance Hair Potion, £16.50, is great for adding volume to lank hair. It will also de-shine it a bit (shiny hair is usually good, but this just looks like a mahogany sideboard), and restore a more sex-kittenish, tousled look.

In terms of make-up, Johansson is lucky in that she can carry a darker, more vampish lip shade. L'Oréal Color Riche lipstick in dark blondes, £7.99, is perfect. For eyes, Prescriptives' new Custom Colour Palette £54.32 (0870 0342566) offers an almost infinite choice of shades, and you can mix and match to suit your requirements. A few soft, pinky golds and rosy browns and she should be back to her glamorous, flirty self.

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