Rocky Carroll is forever grateful to Mark Harmon, whom he credits as his "biggest supporter". Revered as NCIS legends, it's a common misconception that the duo met on the hit TV series when in reality, Rocky and Mark had already co-starred on another show – CBS medical drama, Chicago Hope, from 1996 to 2000.
"I was pretty fortunate because I had a pretty long relationship with CBS before NCIS came on my radar," Rocky told the network's news channel in 2021. "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."
According to Rocky, Mark played a major role in his casting as NCIS Director Leon Vance. "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,'" he recalled.
Speaking about the evolution of his character on the show, Rocky added: "Over time he [Leon] becomes a part of the team, even though he is the head of the organization. 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," he continued. "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 seasons ago."
After signing on to NCIS in 2008, Rocky would go on to work with Mark for the next 13 years. Speaking to Closer Weekly, the TV star raved about the actor's warm nature on set. "Mark's very sensitive to the people around him," noted Rocky.
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"The reason it's such a great working atmosphere is he wouldn't have it any other way. You can just tell the kind of upbringing he had."
A man of many talents, Rocky directed his first NCIS episode in 2015. Given the opportunity to direct a season 12 instalment, the 60-year-old was surprised to learn that executive producers, including Mark, had handed him the reins. Reflecting on the experience, Rocky credited Mark as his "biggest supporter" in an interview with TV Line.
In 2021, Mark would officially wave goodbye to NCIS, although he's since signed on to the upcoming spin-off, NCIS: Origins. And, while Rocky no longer appears on-screen with his old friend, it's clear that Mark has left an indelible mark on Rocky's incredible career.