As the president of Republic Records, Charlie Walk has been involved in helping to launch the careers of some of the biggest artists in the world, and now, he's ready to help break the next big star as part of the panel on FOX's new singing competition series The Four: Battle For Stardom.

If you've been watching, then you're already aware of The Four's intense nature. Each week, four seriously talented performers defend their chairs as they are challenged individually by new singers determined to replace them. If the existing four outperform their challengers, they survive to sing another week, until the end of the season when the final four face off against each other. But, only one will claim the ultimate prize for an aspiring artist: a team of elite star-makers – the series' panel of judges (DJ Khaled, Diddy, Meghan Trainor, and Charlie Walk) – who are all committed to launching and guiding the winner’s music career.

In a new exclusive interview with iHeartRadio, Charlie opens up about how the star-studded The Four panel came together, as well as revealed how he helped to launch the careers of some of the biggest stars in music, including Ariana Grande, Hailee Steinfeld, and Queen of 2017 Julia Michaels.

How The Four Panel Came Together: It all started with a call from Diddy

"I got a call from Diddy, and he asked me, 'Would you join me on this show, where our goal is to have someone win and become not just famous, but affect culture?' He said, 'I've got Khaled on lock,' and I said, 'Well, if we really can do that, I'm in.' And from there I got to call my good friend Meghan and asked her to join us. What happened was the panel is actually a natural collection of friends that have one common goal; to take an artist, help develop them when they win, and put them on iHeartRadio, and put them right into the iHeart On the Verge program, where so many people had number one songs. And that's what's happening on this show."

How Charlie Launched Superstar Music Careers:

ARIANA GRANDE

"One of my favorite stories of Ariana Grande was the beginning of her journey, when KISS-FM in LA played 'The Way,' featuring Mac Miller. And I remember she heard it for the first time, and she called screaming and crying because it was the most important part of her life when it came to recorded music and on hearing her song for the first time on the radio. And from that KISS-FM airplay, it went to number one on iTunes; it started her whole journey to stardom."

HAILEE STEINFELD

"I met Hailee at a dinner right before her 18th birthday. We met and she said to me, 'I'm in Pitch Perfect 2,' and I said, 'I have the soundtrack.' And we started a conversation where she started playing me demos at the dinner of her singing. And she said, 'I can sing just like I can act,' and I said, 'Well, if you were 14 and nominated for an Oscar for True Grit, I'll make a bet on you.' And I never had her perform for us in the offices. I never had her audition. I believed in her."

JULIA MICHAELS 

"Julia Michaels, this year, is nominated for Song of the Year with 'Issues' and Best New Artist for the Grammys. And it actually started at iHeart, as she became iHeart's On the Verge artist, the beginning of last January. It was great to see that happen because Julia was a writer that had over 10 billion streams. She wrote songs like 'Sorry' for Justin Bieber. I identified her early as this amazing artist when I heard the demos of those songs, and I just wanted to know who that girl was on those records singing her own lyrics. And it was Julia. And it took a minute to convince her to be the artist that she is today, to actually believe she was the artist. About a year and a half later, [and] she's become one of the most important singer/songwriters in the world."