Season 9 of The Voice is set to premiere on Monday (Sept. 21), but fans can see one of the highlights from the first episode a few days early.

In the teaser clip above, the coaches perform a medley of their own hits, but with a twist — each coach performs a cover version of a song made popular by one of the other coaches.

Gwen Stefani kicks things off with a cover of Blake Shelton’s “Neon Light,” and Shelton reciprocates with a performance of No Doubt’s “Don’t Speak.” Pharrell Williams turns in a cover of Maroon 5’s “Sugar,” and Adam Levine wraps it up by covering "Get Lucky," Williams' collaboration with Daft Punk, which ends up with all four superstar coaches onstage together.

Shelton returned to work on the set of the show just days after his divorce from Miranda Lambert was announced. He's drafted his good friend Brad Paisley as an adviser to his team, and to lend moral support as well.

“He’s really been good to me, and so the fact that I was able to get him here and and advise my team made perfect sense to me because he was actually a mentor for me,” Shelton tells People.

“If you know anything about country music, you know who Brad Paisley is. He’s Entertainer of the Year. He’s Male Vocalist of the Year. He’s sold millions of albums, and sold out tours,” he reiterates. “He’s just one of the more respected singers, and just people in the music industry and Nashville.”

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