Michelle Trachtenberg Turns 21

TMZ's cameras and our very own Josh Levine hit the streets of Hollywood to catch all the action.

Michelle Trachtenberg celebrated her 21st birthday on Wednesday and we caught up with the stunning actress as she made her rounds, hitting up Hollywood hotspots Koi and Hyde. The "Buffy the Vampire Slayer" beauty had dinner with a few friends at celeb-friendly Koi then made her way to our favorite after party spot Hyde, where she can legally enjoy a cocktail for the first time?!

Also stepping out on Wednesday funny man Anthony Anderson, famous house guest Kato Kaelin, former "Lost" star Michelle Rodriguez, Fall Out Boy bassist Pete Wentz, comedian Jon Lovitz and "Grey's Anatomy" star Sara Ramirez who hosted Tu Ciudad's Hip Hot Now 2006 Party.