
There is an evolutionary reason why the human bum is shaped as it is.
It makes it so much easier to sit on the fence.
Witness this precarious survival technique in action as hapless staff at US Vogue try to appease their scary editor Anna Wintour in The September Issue.
The film charts the production of the most important issue in Vogue's calendar - the September issue which heralds all the fashion trends for Autumn/Winter and carries the most advertising.
The issue ended up at over 4lbs which was the average weight of one of its models.
Anna was parodied by Meryl Streep as the terrifying Miranda Priestley in The Devil Wears Prada. That was terrifying enough without knowing that Anna is like that in real life.
She can make or break designers and reduce executives to tears without taking off her trademark sunglasses.
Even stars are put in their place. Covergirl Sienna Miller is icily fawned over when she meets Anna but behind the scenes Vogue staff bitch about Sienna's thin hair and 'toothy' teeth - whatever that means.
The one person who stands up to Anna is magnificently batty creative director Grace Coddington.
Grace was a '60s model from Wales who posed for all the greats like Bailey and Parkinson before her career was ended in a car crash.
Her beautiful face was ruined but she's gone on to produce beautiful pictures for Vogue.
Business-minded but creatively pedestrian Anna couldn't do without stylistic genius Grace. And though Anna is the boss, she knows the debt she owes.
Their relationship is fascinating. One clear star emerges here, and it's not Anna. Wonder how she feels about that.
The September Issue out in cinemas now and on DVD on 21 September.
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