During a recent benefit concert held Sunday in Los Angeles in order to help victims of the Woolsey Fire that struck Malibu, a few surprises had fans turning on their cell phones and pressing play. One of those surprise moments happened when comedian and actor Jack Black popped in to perform “Sexx Laws” alongside Beck.

According to Rolling Stone, Black showed up midway through Beck’s act, sporting a wicked beard and colorful shirt. As he sang beside Beck, moving around the stage in a Jack Black fashion, the audience cheers grew with every movement.

Towards the end of the set, Beck and his band had riffed through “Where It’s At” to include bits from Chic’s “Good Times,” the Rolling Stones’ “Miss You,” New Order’s “Blue Monday,” Talking Heads’ “Once in a Lifetime” and Phil Collins’ “In the Air Tonight.” Beck also performed by himself with “One Foot in the Grave.” Black returned with his own medley of classics including the Doors: “The End,” “Touch Me” and “L.A. Woman.”

A clip of the performance, which can be viewed below, was taken by someone in the audience and though shaking a bit can see both artists having fun on stage despite the reasonings of the benefit. Black, who appeared to have brought along a piece of sheet music, was smiling the whole performance. Judging by the reaction at the end of the clip, it was clear that everyone in attendance was smiling along with them.

Watch the surprise performance below.

Photo credit: Kalyn Oyer