Billie Eilish's Second-to-Last 2022 Show Featured Surprise Duets with Dave Grohl and Phoebe Bridgers

Billie Eilish is wrapping up the holiday season with a special gift to fans who made it out to her most recent show in Los Angeles.

The "Happier Than Ever" singer, 20, surprised her audience at the Kia Forum Thursday night with surprise guest appearances by Dave Grohl and Phoebe Bridgers, each of whom joined the star for an acoustic song.

First up was Foo Fighters frontman Grohl, who brought out his guitar to sing the band's 1998 hit "My Hero" with Eilish.

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The rocker, 53, explained how much it meant to him that Eilish paid tribute to his late bandmate Taylor Hawkins at the 2022 Grammy Awards in April.

"You know, I have to say, earlier this year, all of Foo Fighters' families gathered together at my house to watch the Grammys, and when Billie came out for her performance in the Taylor Hawkins T-shirt, the room was filled with real tears of love and gratitude," he said. "So from our families, who are here tonight, the Hawkins family, and everyone, we'd like to thank you very much for that. So let's sing it for Taylor. This song's called 'My Hero.'"

Eilish performed at the Grammys just over a week after Hawkins' tragic death at age 50, and sang "Happier Than Ever" while wearing a custom oversized Willy Chavarria T-shirt that featured a photo of the drummer's face on the front and his last name printed on the back in capital letters.

Scott Legato/Getty; Matt Winkelmeyer/Getty; Mauricio Santana/Getty Dave Grohl, Billie Eilish and Phoebe Bridgers

Grohl has also been a longtime fan of the star's, and said in 2019 that his daughters were "obsessed" with her music.

"The connection she has with her audience is the same thing that happened with Nirvana in 1991. … People say, 'Is rock dead?' When I look at someone like Billie Eilish, rock and roll is not close to dead!" he said in an interview with Live Nation CEO Michael Rapino.

After the pair finished their song together, Eilish had another surprise up her sleeve in the form of Bridgers.

"What's up?" Bridgers said as she ran out on stage. "Damn. This is so cool, dude. I'm like shaking, this is so cool. Okay, everybody close their eyes and then I'll be way less nervous. I'm kidding, I'm kidding."

Together, they sang Bridgers' 2017 track "Motion Sickness," with Eilish handling harmonies as well as the second verse.

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Bridgers is no stranger to a surprise concert appearance; last month, she popped up at The 1975's L.A. show to sing "Milk," a deep cut off their second EP.

She's also made her fandom of Eilish known, as she covered the song "When the Party's Over" in a March episode of her radio show Saddest Factory Radio.

Eilish has one final show in L.A. scheduled for Friday night, and then will take a break until she heads to Latin America for a series of festival dates starting in March.