Gene Simmons attended the Foo Fighters’ show on December 4 in Las Vegas and made a brief appearance on stage.

In the fan-shot video below, guitarist Chris Shiflett is seen playing the riff from KISS’ “Calling Dr. Love.” Dave Grohl then cuts in and says, “We can’t do that in front of Gene Simmons!”

Grohl then continues the banter and throws in some Hebrew and Yiddish saying, “Gene, l’chaim. I love you. I love your punim! Hold on a second…Gene! You’ve gotta at least show them your punim! Just show them your f—ing punim! Just one little tiny peek.”

Simmons then emerges from the side of the stage wearing a face mask, approaches Grohl and hands him a dollar bill of some sort. (The amount is unknown.) Grohl then puts the bill in his back pocket and said, “I feel like that’s what you used to look like when you dated Cher. He had the f—ing thing over his face.”

Grohl would go on to say, “I had posters of that motherf—er on my wall when I was a kid. Hold on, let me rephrase that. I still have posters of Gene Simmons on my f—ing wall at home.”

Once again, you never know who might pop up at a Foo Fighters show.

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Erica Banas is a rock/classic rock news blogger who's well-versed in etiquette and extraordinarily nice. #TransRightsAreHumanRights