The 24-year-old singer wore a plunging black top held together with laces down the front and coordinating black skater-style skirt, which was held at the Royal Courts of Justice.
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Flirty skirt: Nicola Roberts wore a plunging corseted style minidress to the Vivienne Westwood show and after-party in London last night
Miss Roberts accessorised her outfit with a pair of black shoes with gems across the toes and on the heels, together with a bright red heart-shaped Westwood handbag.
She stole the limelight from other guests at the show, including Kate Moss, Naomi Campbell, Pixie Lott, Jo Wood, Tracey Emin and Janet Jackson.
The sister of late pop superstar Michael arrived at the show wearing a grey blazer jacket, a black blouse, black trousers and an unusual pair of ankle boots.
She stole the limelight from other guests at the show, including Kate Moss, Naomi Campbell, Pixie Lott, Jo Wood, Tracey Emin and Janet Jackson.
The sister of late pop superstar Michael arrived at the show wearing a grey blazer jacket, a black blouse, black trousers and an unusual pair of ankle boots.
Chic: Roberts chats to T4 presenter Jameela Jamil (left) at the show
The singer was pictured sitting with T4 presenter and former model Jameela Jamil, who wore a peach dress with white polka dots with peach heels.
Chart-topping pop singer Pixie Lott, who also attended PPQ's catwalk show, was at the event wearing a check waist-length blazer over a black dress, tights and heels.
She also sported a cute black bow in her hair and a swallow pendant.
Pop starlets: Pixie Lott and ex-Sugababe Keisha Buchanan enjoyed the fashion show and the after-party
Interest: Nicola is a keen follower of fashion and has already been spotted front row at several London Fashion Week shows
She was often seen as the dowdy member of the group, but has since embraced fashion, regularly attending shows in both London and Paris.
Just last month she was pictured wearing a pair of pop socks on a visit to the Radio 1 studios.
Time to relax: After the show Vivienne headed to the after-party with model Kate Moss and partner Andreas
Icons: Designer Vivienne Westwood with supermodel Kate Moss
She said: 'I remember looking around at my first fashion party a year ago and thinking, "Oh. My. God. This is all about odd people. This is where I fit in."
'It’s my different thing and, in the fashion world, that’s ok. You celebrate it. It’s given me the confidence to experiment with my clothes, with my hair and the way I look.
'I'm just finding out who I am, what my style is,' she told Grazia magazine.
'Everything I wear, I wear because I love it.'
Careless: A worse for wear Kate Moss was among the VIPs at Vivienne Westwood's Red Label catwalk show last night
Fans: Vivienne Westwood with Janet Jackson and supermodel friend Naomi Campbell
Fashionista: Pixie Geldof backstage and on the catwalk at the Westwood show
Tamara Abraham
For a woman who claims not to know much about fashion, last night's show at the Royal Courts of Justice was about as fashion fabulous as it gets.
Dame Vivienne Westwood put on a collection that seemed made for taking on the world.
Fierce-looking models with hair teased into huge distressed beehives strode the catwalk in warrior-inspired ensembles, from military-style coats and pirate boots, to superhero capes and headwear.
Warriors: Strong shoulders were a key theme, and even the most ladylike of dresses was teamed with tough-looking pirate boots
So it would seem impossible that the legendary designer's initial description of the collection included the words 'romantic' and 'fairytale'.
But, for Westwood, a fashion collection is never just about the clothes, and her inspiration told of a romantic ideal based on a love of art and 'loyalty to Gaia' - her way of drawing attention to a scientific theory based on global warming.
In an interview with Stylist magazine, she explained: 'I decided to use my fashion to get across this message that we have to get engaged with the world we live in and stop its destruction.'
Superheroes: The collection featured headwear ready for taking on the world
Describing the woman who might wear the collection in a pre-show statement, she said: 'The woman is an art-lover. Art gives meaning to her life and courage to face the world.
'Her hero is James Lovelock, the 90-year-old genius who unfurled the Gaia theory of science.'
As well as the Gaia message, the collection included a T-shirt designed to raise money for Naomi Campbell's Fashion For Relief charity, which is currently supporting 240,000 pregnant women and new mothers in Haiti.
The T-shirt, which was sported by the designer herself, featured a black-and-white photograph of bare breasts, with 'vital statistics' about Haiti and climate change written across the front.
Message: Westwood used the show to raise awareness about global warming
And it was humorous too. One model stalked the runway while sharpening a knife in an apron bearing the words 'Loyalty 2 Gaia', while the finale - to Rossini's William Tell overture - saw two girls stride out hand-in-hand, only to race back as if they had forgotten to bring Westwood for her bow.
The models appeared to be having a ball, creating an infectious happy energy that had even the most stern-faced editors grinning from ear-to-ear.
It was a show that, in short, reminded us not to take fashion too seriously - that it is there to enjoy, but the world has greater things to worry about. And for that alone, Westwood is our superhero.
Vivienne Westwood, centre, joins her models as the audience applaud her her autumn/winter 2010 Red Label collection