The 1975 were the big winners at the Brits, taking home the awards for best British group and album of the year.
Singer Matty Healy used his acceptance speech to criticise misogyny in the music industry.
Eagle-eyed viewers will have known about the band’s Brit Awards victory in advance, after a TV channel broadcast an advert congratulating them hours before the ceremony started.
The band didn’t acknowledge the mix-up during the awards show.
Elsewhere at the ceremony, George Ezra and Jorja Smith won best male and female respectively.
George, who performed his number one single Shotgun at the event, called the award “the icing on the cake”.
But Anne-Marie, who went into the ceremony with four nominations, left empty-handed.
Calvin Harris bagged his first two Brit awards – after 16 nominations – for music producer of the year and best single, for One Kiss with Dua Lipa.
He said on stage at London’s O2: “I’ve been coming here for a few years and never had the opportunity to say anything.
“I want to thank anyone who bought a tune, streamed a tune, come to show, or even heard a tune by accident on the radio and thought ‘what’s this?’.
“It means a lot.”
One Kiss spent eight weeks at number one and was the best selling single of 2018.
The pair now have five Brit awards between them – Dua won best female and British breakthrough act at last year’s show.
The show was packed with performances from some of the biggest British artists, including The 1975, Jess Glynne and Jorja Smith.
Hugh Jackman opened the show with the theme song to the hit film The Greatest Showman, with his performance featuring hundreds of dancers, acrobats and fire-breathing extras.
The movie soundtrack, which was not nominated for any awards, was the UK’s best-selling album of 2018.
Little Mix won best video for Woman Like Me, which they performed on the night, and admitted they had “absolutely no shame in asking fans to vote for it every day”.
This year’s international winners were noticeably absent, with best male and female winners Drake and Ariana Grande sending in pre-recorded acceptance speeches.
The Carters, who won international group, restaged their famous video shot in the Louvre.
However, instead of posing in front of the Mona Lisa, the couple stood next to a portrait of the Duchess of Sussex.
Pink took home the outstanding contribution to music award, before taking to the stage to perform one of her trapeze routines.
She said in her acceptance speech: “To be considered in the same category as David Bowie and The Beatles and Sir Elton and Sir Paul and Fleetwood Mac is beyond anything I can comprehend.
“It’s been an awesome journey from busking… to playing Wembley Stadium this summer. It’s really exciting!
“Thank you for having me here. it’s been an awesome 20 years. Here’s to 20 more.”
Analysis – Mark Savage, BBC Music Reporter
We’ve always suspected that award show winners get the nod before the ceremony.
If you watched The Grammys last week, you’ll have seen Drake announced as the winner of best rap song – at which point a camera was conveniently pointing at the star, who had arrived, unannounced, backstage as he came out to accept the award.
Tonight, UKTV Play gave the game away completely by broadcasting a pre-recorded advert for “double Brit award winners” The 1975, before the ceremony had even started.
Does it matter? Probably not, although it shines an awkward spotlight on every tearful “this was so unexpected” acceptance speech you’ve ever seen.
And of course, not every award-winner is secretly told in advance. Otherwise, the Oscars’ Moonlight mix-up becomes even more bizarre.