‘NCIS’ Star David McCallum on What Happened Between Mark Harmon and Don Bellisario

NCIS has always boasted a talented ensemble. From the days of Michael Weatherly and Cote de Pablo to newcomers Emily Wickersham and Diona Reasonover, the show relies on its character dynamics to succeed. The procedural has managed to stay on the air for 17 seasons and counting, in large part due to the characters (as opposed to the episodic catch-the-killer narratives). Yet, no one would argue that Mark Harmon’s Agent Gibbs is a significant factor in the show’s triumphant run. 

As many actors leave the series, Harmon remains committed to the show. And, today, he is not only the leading man but also an executive producer on the series. 

David McCallum NCIS
David McCallum ‘NCIS’ | Cliff Lipson/CBS via Getty Images

In the show’s early days, some discrepancies between Harmon and NCIS’s original showrunner, Don Bellisario, led to the latter’s departure. During an interview with DigitalSpy, David McCallum (Ducky) discussed what he remembers regarding Bellisario and why the man behind the franchise left.

David McCallum on Don Bellisario’s departure from ‘NCIS’ 

McCallum played the NCIS Chief Forensic Medical Examiner for many years. He remembers the show’s early days, specifically how it was a bit hectic at the start when it came to the scripts. He said: 

Don Bellisario worked as an advertising executive, even when he was writing scripts, and he loved to work to a deadline…After a couple of years, we got to the point where we were getting scripts late from him. There was a little problem between Mark Harmon – who was representing the cast and crew – and Don, so CBS decided that Don would leave us.

David McCallum | DigitalSpy 

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McCallum explained that Bellisario would send scripts quite late, which likely made it difficult to “work to a deadline,” as Bellisario liked. Though he avoids going into great detail, it’s clear that Bellisario and Harmon were not on the same wavelength. And, CBS chose to keep its leading man, replacing the show’s creator. Who stepped in to replace Bellisario? 

Gary Glasberg replaced Don Bellisario as the ‘NCIS’ showrunner, and then Steven D. Binder replaced Glasberg

Glasberg was a television writer and producer. His production company, When Pigs Fly Incorporated, has been behind a few memorable shows and movies. Glasberg is largely known for working as the NCIS showrunner and developing the spinoff series, NCIS: New Orleans. 

Glasberg also worked as a producer on The Mentalist, Shark, You Ask They Tell, Bones, The Evidence, Laws of Chance, Crossing Jordan, and more. Glasberg died in 2016, and Steven D. Binder stepped in to take over his NCIS responsibilities. Binder is a screenwriter and producer who has worked on Totally Baked, Journey to the Flames: 10 Years of Burning Man, and more.