How can a 29 cm high piece of plastic with nylon hair, an over-sized head, breasts and ankle bones that are permanently shaped in kitten heels position– cause such debate around the world?

How has Barbie, the Mattel doll that’s been around for 64 years, become a prism through which we define the very essence of feminism?

Right now, the new Barbie movie is opening across the world, starring Margot Robbie and Ryan Gosling, and the known universe is divided as to its possible entertainment value (how can live actors play one dimensional dolls?) But the film’s arrival prompts an even more important question beyond ‘Are grown ups who wish to see Greta Gerwig's new film a couple of dolls short of a collection?’ It demands that we ask if the Barbie story is one of female empowerment - given Barbie has been an astronaut, a politician and a deep sea diver -  or is she simply a self-obsessed clothes horse defined by little more than an obsession for pink?

We are now being asked to re-ask ourselves a fundamental issue; are  little girls wrong to want to play with Barbie dolls?

Let’s consider the backstory of the blonde which has sold more than a billion units across the world. Back in the 1940s, a German tabloid came up with a comic strip character known as Lili, a post-war gold-digging blonde who got by in life not by becoming an airline pilot but in seducing men with cash.

Now, feminism was yet to be invented, as we know it, but it’s likely the movement wouldn’t have considered Lili to be an exemplar.

Anyway, such was the success of Lili, in 1953 the newspaper had her made into three-dimensional form, which was sold in newsstands and bars as an adult novelty toy, given out to men at stag parties and the like.

The little doll went down a storm. And not just with older men. Little girls who came across Lili loved the fact she had a range of interesting outfits and wanted to dress her up and play with her.

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Not surprisingly, toy company Mattel acquired the rights to Lili (who was then put to bed for good) and on March 9, 1959, Barbie Millicent Roberts was born, (looking exactly like Lili, if a little more Californian in skin tone) but dressed a little more tastefully.

Not long after Barbie acquired a boyfriend, Ken, a best friend, Midge, and a little sister, Skipper. And over the years, 1968 Barbie was given a series of  'friend' dolls of colour. In 1980 the Barbie doll itself was released as a Black and also 'Latinx' woman.

The Herald: Margot Robbie stars as Barbie in the new movieMargot Robbie stars as Barbie in the new movie (Image: Warner Brothers/PA)

But what of the feminist position? Barbie still looked sexy. She still looked like a vacuous clothes hanger.  She was still seen as a bimbo, (an issue seized upon by Brit doll makers Pedigree who came up with rival Sindy in 1963.) Should young girls aspire to be a creature which, in 1994, researchers in Finland reckoned if Barbie were a real woman, she would not have enough body fat to menstruate? Her vital statistics of 39-16-33 were indeed only physically possible if she’d had all her ribs removed, and 90% of the fat hoovered out of her tummy.

Indeed, an early Barbie came with a diet book which actually said, ‘Don’t eat’. This is very good advice if you’re made of plastic, but not so good if you’re a human little girl.

This doll certainly represented an idealized image of femininity. And in offering up this distorted sense of ‘beauty’, raised serious questions about how she contributed to young girls’ body image issues.

To be fair to Mattel, the company has worked to address the issues; Barbie has had breast reduction, fat attached to her bum and hips, her neck length reduced. And in career terms she has emerged as a doctor and a rock star, a computer engineer, and even president (Andy Warhol was inspired by the doll and painted a portrait of her.)

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Mattel also argued that Barbie suggested ‘You can be anything you want’. But did little girls imbue their Barbies with symbolism - or simply brush their synthetic hair and stick lipstick on their tiny mouths. Were they encouraged to ‘Dream big’, or worry about how their Barbie could achieve big hair?

And did Barbie really leave the sexiness behind with Lili? Yes, Barbie went to the moon before other women had credit cards. But for the most part she still looks like she’s dressing up to meet a Premiership footballer in a bar, or an Arabian prince. If Sindy were the girl next door, Olivia Newton John, Barbie still looked like Debbie Harry if dressed by Balmain.

To be fair to Barbie however, she’s never strayed past Ken. She’s never looked for a sugar daddy. She’s the sort of person that Coutts would be happy to have open an account. But should the kitten heal wearer be regarded as a feminist tiger?

That was clearly the dilemma facing Greta Gerwig when Margot Robbie bought the rights to make a Barbie movie. How to give a one-dimensional, superficially attractive but insipid young woman, a meaning. Gerwig said: 'Barbie is literally plastic. She's unchanging. If you threw her out, she just wouldn't disintegrate. If I could give that persona some humanity, some falling-apart-ness, that – in and of itself – would be meaningful.’

But how? The film opens with the Space Odyssey theme, suggesting that humans inevitably corrupt everything good through a violent thirst for power. The film seems to link to this by suggesting that while Barbie has set out to be good and tells people Go Girl, her true appeal and power are confined to her sexual appeal, physical attractiveness and her ability to coordinate an outfit.

The writer/director knew implicitly you can’t tackle Barbie without taking on shallowness. And so, what she does is introduce the Stereotypical Barbie (the one played by Robbie) to the real world. Now, we have Barbie confronting issues such a death, greed and poverty, shame and grief and ego - and not simply wondering if gingham pink is so last year or not.

Does the film work? Will it help reposition Barbie in the minds of those who think she’s the opposite of what feminism is about, or will she help reinforce the Mattel message that Barbie represents change and possibility?

The Herald: The new Barbie movie could change perceptionsThe new Barbie movie could change perceptions (Image: Warner Bros/PA)

What we do know about this movie on the life of the doll and her cohorts is that Ryan Gosling is perfect casting to play a plastic man. What we do appreciate is that Ken should be given more focus, given the sense of emasculation so many men have felt in recent times.

But the film certainly does offer up great scope for conversation. And it should be fun. Greta Gerwig has proved with Lady Bird and Little Women she’s an awesome talent.

And there’s no doubt it certainly hints at a subversive idea, in taking a dressing up doll and realigning her as a critical voice on superficiality and a shout out for progressivism. But in doing so aren’t you throwing the essence of Barbie into the smelter?

And does it deconstruct the feminist iconography of Barbie and recontextualise her for a new generation? Do the many versions of Barbie represent a symbolic malleability in womankind? Or is she still a bimbo with a great line in clutch bags and a boyfriend who’s simply a partner to match outfits with, a creature without even a hint of a penis, literally and figuratively?

Yes, lots to think about while filling your face with popcorn and slurping your litre of expensive ginger. In offering up hard-earned money to see this movie are you encouraging the next generation of little girls to experiment with different styles, occupations and narratives? Does Barbie now provide a blank canvas for self-expression and foster a sense of agency?

And can the film offer clever metacommentary while asking the deeper question; who are any of us really?

Or is it simply a chance for a film company to make squillions by dressing the ultimate pink clothes horse up as something far more interesting.