For alt-rock fans with long memories, Johnny Depp isn’t just a world-famous actor, he’s also the guy who played guitar and bass for Butthole Surfer frontman Gibby Haynes’ short-lived group P. But for pretty much everyone else, the sight of Depp rocking out with Alice Cooper on a London stage comes as a shock.

Depp joined Cooper for the latter’s show in London’s 100 Club over the weekend, an appearance teased by Cooper when he posted a backstage picture to his Facebook account with the caption “Johnny Depp!! Waiting to jump on stage with Alice for ’18′ and ‘Schools Out!’”

Depp proceeded to do just that, after Cooper introduced him to the crowd by joking, “I think we could use another guitar player, right? Johnny, this whole movie thing … If it doesn’t pan out, join us, okay?”

Cooper’s next album, scheduled for a fall release, will be a sequel to 1975′s hit ‘Welcome to My Nightmare.’