By Alexis Tereszcuk - Radar Entertainment Editor
The engaged Justin celebrated his night out at Surrender Nightclub at the Encore Las Vegas where he and his buddies were dressed to the nines in "Rat Pack" themed suits and "partied in splendor inside a private bungalow overlooking the expansive palm-tree lined and beautifully lit nighttime pool party scene," an eyewitness told RadarOnline.com.
The guys were sipping on Justin's own 901 Tequila and cooled off their steamy night with a late night dip in their private bungalow heated infinity pool.
JT wasn't the only celeb on site, Timbaland and his wife Monique were checking out the music by Rome of Sublime and stopped by to wish their old buddy best wishes on his upcoming wedding.
Now it's Jessica's turn to party down with her girlfriends at her Bachelorette party!
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