Britney Spears Rocks Vegas with Surprise 'Femme Fatale' Performance

Britney Spears gave Sin City a thrill on Friday night, when she performed a surprise set of songs from her forthcoming Femme Fatale album. The 45-minute show -- Spears' first live performance since her 2009 Circus tour -- was kept top-secret until Friday night, when Spears couldn't resist spilling the beans on her Twitter.

"Looks like my little secret isnt a secret anymore. Whos coming to watch me take the stage TONIGHT @RainLasVegas at @PalmsLasVegas?" tweeted the pop star, adding, "You're all invited. Be there are be square bitch!"

Spears was booked as a "special guest" under -- of all people -- DJ Pauly D of Jersey Shore. (She tweeted an image of the marquee here.) After DJ Pauly's set at the Palms Casino Resort's Rain nightclub, Spears performed three songs -- complete with costume changes, sets and back-up dancers -- for the crowd of around 1500.

Spears began with her current single, "Hold It Against Me," which she sang in front of a prop electric chair. For the next number, "Big Fat Bass," she changed out of her sequined bodysuit and into a sexy black leather outfit with a policeman's cap. She belted out the song from inside a giant boombox while her boyfriend Jason Trawick watched from the VIP area.

As her finale, Spears performed "Till the World Ends," dressed in the night's most attention-getting costume: a corset with blinking red lights around the breasts (perhaps a logical next step after Katy Perry's firework bra and Christina Aguilera's light-up crotch). Spears finished the show in this triumphant pose -- and if that doesn't say "Britney's back, bitch!" then we don't know what does.

The performance, which got raves from the crowd, will air next week as part of an MTV special on Spears. All three songs are featured on her album Femme Fatale, which drops on Tuesday, March 29.