What do you get when you get Gwen Stefani and Eminem in a recording studio together? You get the insanely cool song "Kings Never Die," which just dropped on Friday and will be one of many new Eminem tracks featured on the upcoming Jake Gyllenhaal boxing drama Southpaw.

So how did the No Doubt front woman and the iconic rapper get together to collaborate on this new single? Stefani recently sat down with ET to dish about how "Kings Never Die" came to be.

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"He's so incredible. He's a real artist. He's a real weirdo," the singer said of Eminem during a 'Beauty Con-hosted tea party to celebrate wide release of Gwen Stefani's Harajuku Lovers fragrance and launch of Harajuku Lovers accessories. "I just finally got the call. It was one of those days where they were like, 'Can you come do this?' And I was like, 'Really? Really?' And they were like, 'It has to be done today.' And I was like, 'Ok!' And I just made it happen."

However, it wouldn't be as simple as that! As it turns out, the timing was almost terrible.

"I went down there and my voice happened to not be working that day, and I was like, 'Ok perfect -- like, the one time I get asked to be on the Eminem song!?' I don't know - I just prayed really hard and the engineer made it come to life," Stefani said.

But the real craziness came when the rapper called her up to thank her -- but she happened to be driving her kids to soccer practice at the time.

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"I'm driving, literally driving in the minivan with all my kids in the car... and on Bluetooth, somebody calls. And I'm like, 'Hello?' And it was him!" Stefani recounted. "And he's like, 'Hey just wanted to say thanks for doing the song. And I was like, 'You don't understand -- I have all my kids in the car. You can't call me right now. All my kids are in the car! Don't say any bad words!' I was literally going to soccer practice. But I was like, 'I'm gonna make your song so cool!'"

And there's no doubt that she absolutely helped to make the song awesome.

Check out the interview to hear more from Stefani about shooting an all-new season of The Voice.



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