(CBS Local)– “NCIS” starring Mark Harmon is in its 18th season on CBS and actor Rocky Carroll remembers saying to himself that he was happy to be joining a hit show at the end of its run when he jumped in for the fifth season. Little did he know that the next decade of his life would be dedicated to this hit series.

Carroll plays Director Leon Vance on the series and he directed Tuesday’s new episode of “NCIS” called Gut Punch. CBS Local caught up with Carroll to discuss what it was like to direct again, how a previous relationship with Harmon helped him get this gig and why this show resonates.

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“I’ve been given a nickname at work when I’m behind the camera. I’m now Director Director because I play the director and I am the director,” said Carroll, in an interview with CBS Local’s DJ Sixsmith. “This all came about maybe five years ago now. I was curious and I told the producers I’d like to shadow the director. I had been entertaining the idea of directing. About six weeks later, I was given my first shot. I guess I must have done something right because now I’ve got 10 or 11 episodes of “NCIS” under my belt.

The actor and director has appeared in over 300 episodes of “NCIS.” He loves working with the actors when he directs and Carroll has had a friendship with the show’s star Harmon going back to the 1990s.

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“I was pretty fortunate because I had a pretty long relationship with CBS before NCIS came on my radar,” said Carroll. “I had worked on several CBS shows. Mark Harmon and I actually met on “Chicago Hope” back in the 90s. We were both members of the cast of “Chicago Hope” for three seasons. The next time I saw him was during the end of season five of “NCIS.” My audition had less to do with me auditioning and more to do with Mark Harmon saying ‘I know this guy, I like him, you should hire him.'”

Carroll enjoyed the challenge of jumping onto a popular show at the end of the fifth season and making Director Vance three dimensional with many layers.

“Over time he becomes a part of the team, even though he is the head of the organization,” said Carroll. “The writers gave me a lot of leeway with regard to that. Having had a relationship with Mark Harmon prior to that was a huge help as well. We just have fun going back and forth. The amazing thing is I joined the cast of this show at the end of season five and I literally thought to myself that I came in on the tail end of a really good thing. At least I can say I’ll be here for the last two seasons. That was 14 season ago.”

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Watch “NCIS” Tuesday nights at 8pm EST/PST and stream the whole series on Paramount+.