Brian Dietzen is a much-loved fixture on NCIS, known for his alter-ego Jimmy Palmer.
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What's more, the actor is not only starring in the program, but had a hand in writing it too.
Ahead of the CBS show's 450th episode on Monday night, the star opened up about his thoughts on the latest milestone and teased a big storyline should NCIS reach 500 episodes.
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He told Parade: "The 450th episode in its content is not a retrospective in any way. It's going to be another solid NCIS episode. It's going to be more a continuance of the universe as opposed to looking back and seeing how far we’ve come. I have a feeling if and when we get to episode 500 that’ll be something pretty darn special."
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On getting to 450 episodes, he said: "It's a huge milestone. I'll never forget, I think at our 200th episode, I overheard Michael Weatherly doing an interview. He was asked, 'How does 200 feel?'
Brian Dietzen was asked if he thought Mark Harmon would return to NCIS
He smiled and jokingly said, 'Hey, it’s great, we're halfway there.' "All of us started laughing because that’s ridiculous, who's going to make it to 400 episodes? And here we are at 450. I've got to say as a guest star in the first season for one day, I didn't see this happening. But these things happen."
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Brian was then asked whether he believed Mark Harmon - who played Leroy Gibbs in the show for just under 20 years, before leaving in 2022 - would return for the show's 500th episode.
"Who knows?" he coyly replied.
Brian Dietzen plays Jimmy Palmer in NCIS
While it is not assumed that Mark will return to NCIS, his friend and co-star Rocky Carroll, who plays Leon Vance in the show, spoke to TV Insider about the show hitting its 20th anniversary milestone, and whether Mark would reprise his role as Gibbs in honor of the occasion.
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He said: "We might see Gibbs again. I think as long as this show stays on the air, there will always be a little bit of a tease that we might see Gibbs again.” Rocky added: "Gibbs is the moral compass. He's the moral compass that we all wish we had."
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