Blake Shelton handed over the mic to a very special guest during his headlining performance at Long Beach, Calif.'s Coastal Country Jam on Saturday (Sept. 16): His wife, pop superstar Gwen Stefani.

According to a festival recap from the Long Beach Post-Telegram, Shelton's crowd was confused at first when Shelton started strumming the opening lick to Lynyrd Skynyrd's "Sweet Home Alabama" before transitioning into a very different song: "Don't Speak," No Doubt's classic mid-'90s hit. Out walked Stefani, grabbing the mic as Shelton said, "You know I had to bring out the queen, Gwen Stefani, for this night."

From there, he handed the reins over to his wife, who belted out "Don't Speak" to a crowd roaring the words right back to her.

Stefani frequently makes appearances at Shelton's shows, and she's been known to perform her classic No Doubt hits on country stages. At the 2023 CMT Music Awards earlier this year, she and Carly Pearce delivered a live duet rendition of "Just a Girl."

But Stefani's time on the Coastal Country Jam stage wasn't over after "Don't Speak" ended. She rejoined Shelton and the pair sang their two chart-topping country hits, "Nobody But You" and "Happy Anywhere."

Before leaving the stage, Stefani shared a kiss with Shelton, who led the crowd in another round of applause before continuing his solo set.

Video filmed by fans in the crowd also shows Shelton jokingly wondering whether Long Beach has much of a country fanbase.

"Let me ask y'all something. Be serious. Were y'all just walking by here today and you saw there was some stuff going on and you decided to stay here?" he said drily, getting some laughs from fans in the audience. "Or do y'all really like country music?"

Shelton has been enjoying some well-earned downtime in recent months. The upcoming season of The Voice is the first iteration of the show ever to air without him as coach, as he recently retired after being on the show for all 23 seasons since it began. Stefani is holding down the fort as a The Voice coach for Season 24, and the country contingent is well taken care of on the show, too: Reba McEntire is stepping into Shelton's shoes as a country coach.

The new season of The Voice will premiere on Sept. 25 on NBC.

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Ten years (and counting) made a huge difference for many of the most popular singers and stars of The Voice. Blake Shelton looks noticeably different, but so do some of country music's most memorable performers.Winners like Cassadee Pope and Danielle Bradbery wore baby faces when they auditioned during their respective seasons. The same can be said for Morgan Wallen, a forgotten castmember from the show who's transformed more than anyone else on this list of The Voice stars then and now.