David McCallum appeared in 459 episodes of NCIS, making him one of the longest-serving cast members in the show’s history. His portrayal of Dr. Donald “Ducky” Mallard became iconic, earning him a special place in fans’ hearts over the years. However, another star from the series is on track to surpass this impressive milestone.

Brian Dietzen, who plays Jimmy Palmer, has steadily increased his presence on the show with each season. Starting as a recurring character, Dietzen has grown into a core member of the NCIS family. With many seasons still ahead, he is set to break McCallum’s record and become the cast member with the most episode appearances.

Fans have been watching Dietzen’s journey closely, celebrating his growth and contributions to the series. While McCallum’s legacy remains firmly intact, this new milestone highlights the evolving dynamics of NCIS and the importance of longtime actors who continue to shape the show’s success.