Justin Bieber, Miley Cyrus, Katy Perry, Robbie Williams, Take That, Liam Gallagher, and Little Mix were among those who hit the stage.
Fans gathered in Manchester for a star-studded charity concert on Sunday, remembering the victims of a suicide bomb attack following an Ariane Grande concert two weeks ago and vowed to face down fears of terrorism less than 24 hours after an assault in London that claimed seven lives.
A sell-out crowd of 50,000, many of them clutching "For our angels" signs, fell silent for a minute before Mumford & Sons frontman Marcus Mumford opened the show.
Hastily organised as a benefit concert for the 22 people killed and 116 injured on May 22, many of them children, the "One Love Manchester" event showcases one of the biggest single gatherings of musical talent this year.
But on the eve of the concert, Britain was rocked by another terrorist attack in London, in which seven people were killed and 48 injured. Grande tweeted "Praying for London" while her manager Scooter Braun said the concert would go ahead "with a greater purpose."
Fans flocked to the Old Trafford cricket ground for the concert, some posing with police officers while supermarket staff handed out free snacks.
Additional security measures were put in place with police warning that everyone would be searched.
Revellers dressed for the occasion, with many wearing tops featuring a bee — a symbol for Manchester — and slogans expressing their love for the city
."We're here to show our support to Manchester more than anything. These people aren't going to dampen our spirits," said 34-year-old Abdullah Mala.
Security officers stole the hearts of millions as they danced hand-in-hand with young girls in the crowd during the concert.
His eight-year-old daughter Hannah had left the Grande concert just before the deadly bombing and said she was "happy to be back" to see some of the pop's biggest names.
Overcome the fear
Proceeds from the concert will be donated to a fund set up to help the victims' families.
Rachel Jea, 32, said she was at Grande's previous Manchester concert and felt it was important to attend Sunday's show to regain trust after the bombing.
"Our grandparents went through world wars so that we could live in freedom and now it's starting again. It just shouldn't be like this."
Her nine-year-old daughter Scarlet adopted a defiant tone, telling others not to be afraid. "We need to try and find a way to overcome the fear. I'm really happy to come tonight, it is good for Ariana, it wasn't her fault what happened."
TRT World's Sara Firth has more from Manchester.
Ariana Grande, 'broken'
Grande, who described herself as "broken" following the May 22 bombing, immediately returned to the US, interrupting her Dangerous Woman world tour.
But the 23-year-old singer pledged to return for the charity concert, writing on her Instagram: "Music is meant to heal us, to bring us together, to make us happy.
"We will continue in honour of the ones we lost, their loved ones, my fans and all affected by this tragedy," she added.
Grande on Friday made a surprise visit to injured fans being treated at the Royal Manchester Children's Hospital.
Twenty-four children from a local school, some of whom were at the targeted Manchester Arena concert, also joined Grande on stage to perform her hit song "My Everything."
The 35,000 tickets put up for sale on Thursday at £40 each ($51, 46) sold out in minutes with 14,200 free tickets set aside for those who attended Grande's May 22 concert.
"Over 10,000 unscrupulous applications", however, were made for free tickets, Ticketmaster said, with people applying despite not having attended the original concert.
Others tried to resell their tickets on eBay for £1,200. The online auction platform has since then pledged to immediately remove any item "which profits in any way from the tragedy in Manchester."
The BBC, Twitter, Apple, YouTube and MTV announced they would stream the concert live, reaching a potential audience in 180 countries.