BROOKLYN, NY – The Beastie Boys held a secret show in their hometown, and a certain beastly boy was on hand to collaborate.

One of the longest-lived hip hop acts, the Beastie Boys originally started as a punk band but was shaped by famous producer Rick Rubin into a three-man rap crew. They found critical and financial success with hits “So What’cha Want”, “Sabotage” and “Intergalactic”, all of which they performed at their surprise concert at the Music Hall of Williamsburg last night.

During their final song, “Fight For Your Right”, Ad-Rock spotted the one and only Bat Boy head banging in the front row and pulled him on stage. His contribution mainly consisted of shrieking into the microphone, coincidentally harkening back to the band’s hardcore phase.

Bat Boy was so excited he offered them chocolate-covered mosquitoes after the show, but the Boys declined as Mike D. is now vegan.