Instead of a traditional catwalk show, McCartney invited 100 or so of her closest friends for dinner - she was flanked by Vogue editor Anna Wintour and the singer Rihanna, with model Kate Moss close by - and sat at her table applauding when the models emerged unannounced from the dinner crowd dressed in gorgeous evening wear.
They danced on tables, were passed around on chairs held high - almost as if it was a traditional Jewish wedding - and gyrated to raucous music for a brief six or seven minutes, then went up on stage to be joined by the designer.
It was an impressive break with tradition, with the models following a magic show that saw TV personality Alexa Chung apparently suspended in mid-air. The festivities followed a hoity-toity sitdown dinner that featured a live band in tuxedos playing traditional jazz tunes.
McCartney's unorthodox contribution to London Fashion Week seemed to strike a chord, even if it was hard to gauge the sexy, lacy and tight evening wear her models were wearing for their brief spotlight stint. The dresses looked beautifully made and colourful, but it was difficult to judge each one as they swirled by.
"It was a good idea, and she made it work," said former model Bianca Jagger, wearing a signature white suit.
"It was nice to see something different, something dramatic. The clothes looked great. And the food was delicious, " Jagger said.
The menu included duck with black truffles, chestnuts and Jerusalem artichokes, beetroots with Sicilian blood oranges, saffron risotto, and Wigmore cheese with still more black truffles, along with a variety of wines and Veuve Clicquot champagne.
It was a rare London appearance for McCartney, who usually shows her designs in Paris. She was joined at the head table by Rihanna, wearing a dramatic dark green full-length gown with a deeply plunging neckline, and Wintour, who wore a more demure dark dress.
Rihanna's many admirers said she had styled herself after the young Tina Turner.
After the show, an exuberant McCartney declined to give any details about her designs for Britain's Olympic team uniforms, which have not yet been revealed.
"It's a big secret," she said.
Why would she turn to sports gear after a successful career selling gowns, cocktail dresses, lingerie and perfume?
"Because I'm British and it's a huge honour for me," she said.