The 'Toxic' hitmaker started the show by descending from the ceiling on a circular trapeze, wearing a revealing corset and fishnet tights, singing her recent track Circus, reports Contactmusic.
After a month's break from performing since she wrapped up her North American shows in May (09), Spears seemed to be in a dazzling form as she belted out all her classic hits - and surprised concert goers by remixing a selection of her tracks, including Baby One More Time and Womanizer, especially for her European tour.
Spears flaunted a new toned figure in a range of figure hugging outfits, including a raunchy sequined number with nipple tassels and a ringmaster outfit, complete with whip.
The singer stopped during the concert and yelled to the crowd, "What's up London! I am so happy to be here tonight!"