Nashville hit a milestone with the airing of its 100th episode on June 15, but the show hasn't reached its peak.

Creator Callie Khouri talked about the evolution and future of Nashville with the Hollywood Reporter. They cites that though it's in its first season on their network, Nashville is CMT's highest-rated and most watched show ever, with day ratings up nearly 20 percent among viewers 18-to-49 and up 25 percent among women in the same age group. As Khouri explains, it was always a challenge to make the show "as real as we could make it and still have it be exciting enough for ABC."

"The one thing we always resisted was having it be a real catfight situation with Rayna [Britton] and Juliette [Panettiere] because that's just not a positive story for women," she shares. "I was fine to have them in competition — but because they came from different places creatively and not just because women don't like each other."

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Khouri adds that Britton had shown interest in leaving the show throughout the taping of Season 4 due to other opportunities. While it wasn't an ideal situation for the series' story line, she says it was a difficult situation all around.

"It was not easy to let that happen, but you don't want to hold anybody hostage, either," she explains.

The episode filmed of Britton's character's death was an emotional one for viewers and actors alike. In fact, Khouri says the entire cast was in tears. "It was tougher than any of us realized," she adds.

Those interested in learning about where the series is headed are in for a treat and when asked how long Nashville could last, Khouri hints it could be for a very long time.

"There are always new characters and stories to tell. Everybody in [Nashville], as far-fetched as we've been, says, 'Oh, boy, you haven't even scratched the surface,'" she concedes.

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