How ‘NCIS’ Writers Made Sure Mark Harmon’s Gibbs Sounded Authentic in Every Episode

Before a script makes it into TV or film, it passes through several editing processes and decompressing to ensure much of it makes sense. Sometimes, writers face challenges paring down the number of words they want a character to use to convey an idea. But NCIS writers had a way of ensuring Mark Harmon’s character, Gibbs, sounded authentic in every episode.

Mark Harmon played Leroy Jethro Gibbs in over 400 episodes of ‘NCIS’

Mark Harmon: Gibbs, NCIS
Mark Harmon as NCIS Special Agent Leroy Jethro Gibbs | Sonja Flemming/CBS via Getty Images

Leroy Jethro Gibbs is a protagonist in the long-running police procedural crime drama NCIS. The character is a former U.S. Marine Corps scout sniper working as a special agent commanding the Major Case Response Unit of the Naval Criminal Investigative Service.

Gibbs is an accomplished marksman skilled at handling vicious standoffs. He leads a team experienced in technical forensics and background checks. Gibbs is a patient yet firm leader who doesn’t always have the time for bureaucracy.

Over the years, Gibbs’ team has comprised Ziva David, Anthony DiNozzo, Caitlin Todd, Timothy McGee, Nick Torres, Clayton Reeves, Alexander Quinn, Ellie Bishop, Abby Sciuto, and Jacqueline Sloane. Gibbs has been married four times, first to Shannon, then to Diane Sterling. Rebecca Chase was Gibbs’ third wife, while Stephanie was his most recent.

Gibbs first appeared in the legal drama JAG Season 8 Episodes 20 and 21, which also acted as the backdoor pilot for NCIS. Mark Harmon played Gibbs in over 400 episodes until his retirement in 2021.

‘NCIS’ used a ‘Gibbs Pass’ to make the character authentic

Some characters in movies and TV series are meant to be outspoken and wordy. However, some can convey a lot without saying much. Leroy Jethro Gibbs is one of those characters. Gibbs became known for his firm yet silent nature, and throughout his time on the show, he didn’t feel the need to say more than he needed to, conveying much with only nods, gestures, and glances.

But his stoic personality made writing Gibbs’ dialogue challenging. So how did the writers make him authentic? According to Looper, they used a “Gibbs Pass” on the script even after it was done. The Gibbs Pass helped the writers determine if any of the character’s dialogue needed trimming or deletion.

When the writers removed dialogue, they replaced it with nonverbal actions. Still, they couldn’t fill a whole episode with only cues, so they had to strike a balance between his dialogue and nonverbal actions.

Christopher Silber told TV Guide in 2014 that when he began writing for NCIS, a huge chunk of his script got removed. He was told Gibbs could “say that with a look.” However, as time passed, Silber got the gist of the character and finally nailed his dialogue.

Mark Harmon could return, but right now, he’s behind the scenes

Gibbs resigned from his role as the leader of the MCRT, and a few weeks later, the FBI claimed it had a warrant for his arrest. In the episode “Great Wide Open,” Gibbs travels to Alaska to chase down a lead on a string of mysterious murders. He concludes his investigation, but the FBI agent lets him go.

At the end of the episode, Gibbs reveals he won’t return home or to work, noting he has felt peace in Alaska for the first time in a long time.

The open-ended exit left room for Harmon’s return to NCIS. However, for now, Harmon is thriving behind the scenes as the show’s executive producer.

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