Little Mix wowed the crowd at the Capital FM Summertime Ball, where they joined a line-up including Bruno Mars, Stormzy and two of One Direction.
The girl group were a hit with pop fans as they belted out hits such as Black Magic and Shout Out To My Ex to close the concert.
It's the latest triumph of a soaraway year for South Shields singers Jade Thirlwall and Perrie Edwards, and bandmates Jesy Nelson and Leigh-Anne Pinnock.
Unusual outfits were a feature of their act, with Perrie donning a pair of high-waisted denim pants with baggy lower legs which were completely missing the thigh area, while Leigh-Anne'sjeans only had one leg.
One fan tweeted: "@LittleMix was the main reason I went to the #CapitalSTB and boy they certainly stole the show."
Someone else added: "@LittleMix you girls really know how to put on a show. You owned that stage."
Another person tweeted: "Honestly putting little mix at the end was such a great idea they were amazing what a closing I loved them."
Also on the bill at London's Wembley Stadium were two members of One Direction performing their solo material, Niall Horan and new father Liam Payne.
Other X Factor alumni taking to the stage included James Arthur and trio 5 After Midnight.
Acts entertaining the crowd also included Rag'n'Bone Man, Anne Marie, Dua Lipa, Shawn Mendes, Sean Paul and Louisa Johnson.