John Stamos Performs at L.A. Halloween Party as Zombie Elvis

John Stamos surprised attendees at a Halloween event in L.A.’s Hidden Hills neighborhood last night dressed as a zombie Elvis … and — have mercy! — he knocked it out of the park.

Singing “Good Golly Miss Molly” … John was accompanied by a full band who were all dressed up for the big spooky celebration.

During the band’s rendition of “Honky Tonky Women” … the “Fuller House” star switched over to the drums.

Not only did the longtime Beach Boys special guest grace the stage … but Melissa Ethridge also performed — wearing an inflatable alien abduction getup.