Exclusive Pic: Justin & Timbaland's Surprise Performace!

For most performers, the last thing they want to do after a concert is to perform again. But not , who, fresh from his blistering stage show at Vegas' Mandalay Bay on Saturday night, headed over to Jet Nightclub at The Mirage for an after-party that rivaled any of his scheduled tour stops.

Soon after JT strode into the club around 1 a.m., the seven-time VMA nominee, along with superstar performer/producer , who has been put in charge of the music for next week's VMAs, gave club-goers a once-in-a-lifetime experience when they launched into their impromptu concert. The hour-long set of the two music icons' hottest hits had the entire club pulsating into the early morning, when JT and his family and friends made their exit slightly after 4:30 a.m.