As Covent Garden played host to the BAFTAS, just down the road, on the banks of the River Thames, London Fashion Week was in fierce and stylish competition with its own global superstars, red carpet-worthy gowns and the ‘premiere’ of a new movie, starring Sienna Miller.

Miss Miller played a sexy rock-chick in a short film to promote Twenty8Twelve (named for her birthday), the label she designs with her sister Savannah.

The movie was projected onto the wood-panelled walls of the Art Nouveau palace at 2 Temple Place last night, which was originally built for the first Viscount Astor.

It formed a backdrop for models parading the Twenty8Twelve autumn/winter 2010/2011 collection, which was inspired by 1980s underground club culture, in acid-dyed denim and velvet, with hand-crocheted knits.

Earlier, Sienna Miller had taken a break to sit in the front row for the show by the British designer, Matthew Williamson, one of her best friends. Williamson’s collection, inspired by Spain and the culture of the matador, featured fan details on cobalt, purple, and salt-and-pepper tweed suits; fiesta prints; toreador trousers; and dazzling shifts and gowns in gold and silver, based on bullfighters’ jackets.

The singer, Janet Jackson, made a surprise trip to London to sit in the front row for the show by Todd Lynn, the rock ‘n’ roll tailor, who made most of the clothes for her last video, and who has a huge music following, numbering Mick Jagger and Bono among his clients.

Lynn’s taut, tight, strong-shouldered tailoring was expressed in beige and black leather, fox furs and sheared mink, accessorised with sliced leather, gauntlet gloves and cuffed, ankle-boots.

Earlier, Jasper Conran took inspiration from the sculptors Henry Moore, Louise Nevelson and Barbara Hepworth, for a bold and bright collection which focussed on a voluminous “balloon” or “cocoon” top, allied to skinny trousers and pencil skirts. Dresses and suits in poppy-red, emerald, cobalt, pink and orange, featured see-through panels at the navel, midriff, hip and thigh. Red carpet gowns were tethered with halter-necklaces in fluorescent PVC.

Naomi Campbell, who launched London Fashion Week last Thursday night, with her Fashion for Relief/Haiti, was the guest of honour at Vivienne Westwood’s Red Label show last night.

London Fashion Week continues today with shows by Nicole Farhi, Christopher Kane, Jaeger, Paul Smith, Pringle, and Erdem, the designer favoured by the wives of both the prime minister and the leader of the Opposition, Sarah Brown and Samantha Cameron.