NCIS’ Rocky Carroll Reflects on Franchise’s ‘Incredible, Rare Era’ (Exclusive)

As NCIS surpasses 1,000 episodes, Rocky Carroll is reveling in the unique space the franchise has found itself in.

Speaking exclusively with PEOPLE, the actor, whose starred as Leon Vance since season 5, reflects on the franchise’s new “incredible, rare era” and why he believes its been able to endure for so long.

“By the time I joined the show, it was already a very well-established show,” he begins. “It was five seasons in. Before you know it, you look up, and it’s 10 seasons. You’re into a new decade.”

Carroll says that one of NCIS‘ secret to success is its team of producers and writers haven’t “allowed” the show and its characters to remain stagnant in a “certain year or a certain timeframe or at a certain age.”

“The characters have grown and evolved,” he explains. “We evolved over these 20-something years. We’re not playing the characters with the same mindset and sensibility they had 20 years ago. They’re older. All the characters have gone through their own share of peaks and valleys, death, loss, separations, all these different things.”

Despite the changes NCIS and its cast has endured, Carroll notes that the procedural’s characters are “still doing the same job” and working for the same agency. Even though some things have changed and some haven’t, at the core of NCIS is it’s purpose. Carroll says that former NCIS veteran, Mark Harmon, would always say, “The star of this show has to be the agency.”

“It has to be about NCIS. If it becomes about any one person in particular, we probably would’ve been off the air 15 years ago,” he adds.

On April 15, the crime-fighting franchise celebrated its 1,000 episode milestone.

In a statement exclusively shared with PEOPLE, Vanessa Lachey, who made history as the first female lead in NCIS history in its Hawai’i based spinoff series, opened up about what it’s meant to be a part of the millennial milestone.

“It’s an honor to be able to add to this incredible franchise and to do it as the first female lead has meant more to me than I can ever express,” she said. “It shows the incredible evolution and longevity that NCIS continues to give its fans.”

Lachey added that getting to have a “family” both “across the generations as well as continents” is what she loves most about being a part of the NCIS universe.

“Not only with our cast but the fans as well,” she continued. “The NCIS franchise is all over the world and it brings people together to watch and talk about, as well as provide comfort and entertainment, which is what you want when you dive into a show.”

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NCIS airs Mondays at 9 p.m. ET on CBS.