'The Voice': Inside the Show's Epic Coach-Mentor Partnerships

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ET found out what makes the coach-mentor relationships work so well on The Voice.

This season, The Voice coaches Blake Shelton, Miley Cyrus, Alicia Keys and Adam Levine are teaming up with mentors Bette Midler, Joan Jett, Charlie Puth and Sammy Hagar, respectively. While they all have separate styles and come from entirely different backgrounds, there is one common denominator: they're all fans and friends of each other.

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Midler was especially taken with Shelton.

"He's fun, he's cute, he's with it, he's funny, he's witty, he sings great, plays great guitar, sold millions of records," Midler gushed, before joking, "He writes his own songs, and he's going to give me one."

Shelton had equally flattering things to say about Midler.

"I can't think of anybody who knows more about the entertainment industry than Bette," he said.

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Hagar's already making plans to collaborate with Levine in the future, but not in the way you think.

"Adam and I are going to go into business together, sit on the beach, and work when we want," Hagar joked.

"Which is never," Levine chimed in.

While many of the mentors are more advanced in years than their coaching partners, 24-year-old Puth is the rare instance where the mentor is hoping to follow in the footsteps of his coach, 35-year-old Keys.

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"I'm just trying to be like you when I grow up," Puth told Keys.

"Dope," Keys answered.

The Voice airs Mondays and Tuesdays at 8 p.m. ET/PT on NBC.