Kristen Merlin on The Voice episode 615

The Voice "Playoffs" Episode 615. Pictured: Kristen Merlin

 

Trae Patton/NBC

The Instant Save may be annoying to half of the country, and the weekly double eliminations might be occasionally harsh, but the best thing about "The Voice" is that it's a show that constantly changes. So far, season six has knocked out an entire round and replaced it with much better battles, and brought in Coldplay's Chris Martin as a universal mentor to all four teams.

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Monday night's episode brought another surprise: industry mentors for the top 10. Shakira recruited her producer Busbee, Blake Shelton brought in his producer Scott Hendricks, Usher brought his musical director and producer Natural, and Adam Levine called on his own mentor, Crosby, Stills and Nash's Graham Nash. These music biz experts ended up offering professional-level challenges, causing some of the finalists to rise to the occasion while others drowned in high expectations.

After U.K. band Rixton kicked off the episode by performing "Me and My Broken Heart," the top 10 took the stage to vie for viewers' votes. Read the full story over at THR.com.