By Paul Glynn
image copyrightGetty Images
Dua Lipa demanded a pay rise for NHS workers as she won two major awards at the Brits - the UK's first major in-person ceremony of the Covid era.
And Little Mix called out sexism in the music industry after becoming the first all-female outfit to win best British group.
The other big winners on the night were J Hus, Harry Styles and Taylor Swift.
The test event at London's O2 Arena took place with a 4,000-strong audience and no social distancing or face masks.
Elsewhere, rapper Headie One used his performance to criticise the government, while highlighting the work done by footballer and free school meals campaigner Marcus Rashford in one of his verses.
On a leap year, the 2021 Brits were very much a Lipa year though, as the singer won two of the three awards for which she was nominated.
Future Nostalgia, last year's biggest-selling LP in the UK, predictably won best album.
But it was after winning the best solo female gong, her first of the night, that the star called on Prime Minister Boris Johnson to give nurses and NHS workers pay rise, as opposed to merely claps.
This year, each of the award trophies came in two parts and Dua dedicated hers to British nurse Dame Elizabeth Anionwu - who she noted has spent "a stellar nursing career fighting racial injustice" and "protecting frontline workers".
"She has also said that there's a massive disparity between gratitude and respect for frontline workers," said the singer. "Because it's very good to clap for them, but we need to pay them.
"So I think what we should do, is we should all give a massive, massive round of applause and give Boris a message that we all support a fair pay rise is for our frontline."
The applause, at least, was the forthcoming and loud.
Before all that she performed a medley hits from her latest floor-filling record.
It was a visual love letter to her home city of London, complete with Tube celloists and a union jack skirt which evoked memories of Spice Girl Geri Halliwell's famous patriotic dress.
'Male dominance, misogyny, sexism'
The night's big winner also shared her delight at seeing more women on both the stage and the winners' podium - several years after she called for exactly that from the same spot.
Women won four of the five mixed categories.
One such example, Little Mix dedicated their award to some of the great all-female bands who have been overlooked for the award down the years.
"It's not easy, being a female in the UK pop industry," said Leigh-Anne Pinnock while accepting their award.
"We've seen white, male dominance, misogyny and sexism, and a lack of diversity.
"We're proud that we've stuck together, surrounded ourselves with strong women and are now using our voices more than ever."
"The fact that a girl band has never won this award really does speak volumes," added bandmate Jade Thirlwall. "So this award isn't just for us, it's for the Spice Girls, Sugbabes, All Saints, Girls Aloud.
"All of the incredible female bands - this one's for you."
Since the departure of Jesy Nelson, Little Mix are now a three-piece, and two of them - Pinnock and Perrie Edwards - have recently announced that they are pregnant.
Rapper J Hus was not on hand on the night to pick up his award for best male solo star.
But Harry Styles was - in typically well-tailored fashion in a brown and white check suit - to collect best British single for his ubiquitous hit Water Melon.
If last month's Oscars took place in tinsel-town then the Brits was very much tonsil-town, as spectators underwent Covid tests on their way into the event.
The event formed part the government's pilot scheme for reopening live events safely, which includes the forthcoming FA Cup Final.
The live audience of about 4,000 people was about one-fifth of the O2's capacity and more than half of the ticket-holders were key workers from Greater London and their guests.
Several performances were pre-recorded including Coldplay's show opener from a pontoon on the River Thames.
They performed their new single Higher Power with a little help from some holograms and pyrotechnics.
Before the event, US pop star Taylor Swift - who best international group-winners Haim described as "the most incredible human being" - was announced as the first female winner of the global icon award.
In winning the award she followed in the footsteps of Sir Elton John, David Bowie and Robbie Williams.
In the only other award announced before the event, young singer Griff was named as the winner of the rising star prize, and she demonstrated why with a career-defining performance.
Previous winners of the award include Adele, who went on to win a host of more senior Brit Awards in the years that followed, including best female, album and single a couple of times over.
The show finished with a performance from Rag 'n' Bone Man and a virtual Pink, alongside the Lewisham and Greenwich NHS Trust Choir.
Before introducing them, Jack Whitehall, hosting the awards for a fourth time, like many of the big-names on the night gave "a massive big up to the key workers here tonight, and across the country".
"We will never be able to thank you guys enough," he said.
The 2021 Brit Awards winners in full:
Breakthrough Artist: Arlo Parks
Best British Single: Harry Styles, Watermelon Sugar
Female Solo Artist: Dua Lipa
International Female: Billie Eilish
International Male: The Weeknd
International Group: Haim
British Group : Little Mix
Best Album: Dua Lipa, Future Nostalgia
Global Icon: Taylor Swift