Victoria Beckham unveiled a timelessly chic collection in the ornate court of Britain's Foreign Office on Sunday as environmental demonstrators shut the road outside to protest waste created by fast fashion.
The fashion pack were forced to pass their handbags through metal detectors before entering the majestic Durbar Court, where they sat among doric columns of polished granite.
The models sashaying along the marble floor wore long silk dresses in powder pink or purple, and blouses with big collars and houndstooth jackets for an elegant seventies look.
Beckham's husband, ex-footballer David, and their four children -- Brooklyn, Romeo, Cruz and Harper -- were in the front row to watch, alongside Anna Wintour.
"Lightness, easiness, freedom -- those are the ideas I was thinking of for this collection," the British designer, a former member of the Spice Girls pop group, said in the notes for her Spring-Summer 2020 collection.
"There's a play between precise masculine tailoring and floating soft dresses that let the body breathe inside them," she said.
Outside, around 20 Extinction Rebellion activists intercepted guests in a protest against fast fashion, which critics say is one of the world's most polluting industries.
"We are here to protest against that endless obsession with buying new clothes," one said as they held up signs declaiming the "ugly truth about fashion".
The group earlier briefly shut Whitehall, the main road running past government ministries to parliament.
They had gathered on Friday in blood-stained white robes near the entrance of the main London Fashion Week venue in central London as the week kicked off.
- 'A new kind of sexy' -
After years of showing in New York, Beckham made her debut in London last year to celebrate a decade since the launch of her eponymous label.
The clothes this season were in beige, camel or pale yellow, contrasted with grass green or a bright purple, while she also introduced some lively prints set against a darker background.
"The prints are bold, almost luminous... they're not like anything we've done before," she said.
"It adds up to a new kind of sexy -- no restriction, not much skin on show but a sense of the body and of the woman inside.
"For me, it's about that woman really feeling confident and sensual in her clothes."
Beckham initially faced scepticism about her move into fashion, but now sells her clothes at more than 400 locations in around 50 countries.
This week, she launched a new cosmetics line, Victoria Beckham Beauty, with former Estee Lauder executive Sarah Creal.
They have created a streamlined collection without many chemicals commonly used in makeup and with packaging that can be recycled or is biodegradable.
Sales of Beckham's clothes line went up 17 percent to £42.5 million (47.5 million euros, $52.9 million) in 2017.
However, Victoria Beckham Limited recorded an operating loss of £10.2 million in the same year, against £8.2 million a year previously.
But she has no plans to return to music, and did not join her fellow Spice Girls when they held a reunion tour this summer.
While wishing them well, she told the Daily Telegraph this weekend: "There was never a scenario when I closed my eyes and could see myself performing on stage with them again."