On Monday night (April 24), Keith Urban performed a brief set for fans during a Spotify-produced event in Nashville -- and he brought a special guest with him. Urban's wife, Nicole Kidman, watched the show from the back of the room, smiling and singing along as Urban sang; she even playfully heckled the country star a bit, yelling, "Just play it!" when she thought Urban was spending too long talking before launching into the next song.

"I'd know that voice anywhere," Urban responded. "I'll play it if you come up and sing it with me."

It took a bit of convincing from the crowd, but Kidman did eventually make her way onstage, where Urban serenaded her with his new song "Parallel Line," as she sang along to the chorus; readers can press play above to see a brief snippet of the performance. Kidman, seated on a stool in front of the mic, occasionally chimed in on a line or two; until then, she'd stood inconspicuously in the crowd, and even seemed a bit embarrassed to be onstage.

During the fan Q&A that Urban interspersed between songs, the singer fielded a question about which song on the record most reminded him of his wife. "That would have to be "Gemini,"" Urban responded with a laugh; at the back of the crowd, Kidman -- who is indeed a Gemini, astrologically speaking -- nodded and laughed as well.

Monday night's event, which took place at Nashville's Houston Station, was a Spotify Fans First event, for which the music streaming service invited more than 150 of Urban's fans to a curated art exhibit and guitar emporium in celebration of the country star's forthcoming new album, Graffiti U. In addition to Urban's performance and the art displays -- which featured street art-inspired murals created by local artists Nathan Brown, Ty Christian, Brian Wooden, Eric “Mobe” Bass and Aaron Martin -- fans were able to hear the record, which is due out on Friday (April 27), and participate in a Q&A with Urban.

In addition to "Parallel Line," Graffiti U features 12 brand-new songs from Urban -- including one with Kidman on background vocals. She and Nicolle Galyon sing on the song "Female;" Galyon, Shane McAnally and Ross Copperman wrote that song, and Copperman and Dann Huff produced the track.

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