Go Behind the Scenes of ‘NCIS’ With Mark Harmon & the Cast (PHOTOS)

Behind the scenes of 'NCIS' through the years

With now 1,000 episodes and counting to the franchise, we did a little investigating of our own to find out about life on set for Mark Harmon (who played Leroy Jethro Gibbs until his on-screen exit from NCIS in Season 19 Episode 4) and our favorite cast.

Take a peek into the case file by scrolling down for the behind-the-scenes photos, along with insight into a few of the episodes and filming.

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This is an excerpt from TV Guide Magazine’s NCIS: Special Collector’s Edition issue. For more inside scoop on the long-running CBS franchise, pick up a copy of the issue available on newsstands and for order online at NCISMagazine.com.

Monty Brinton / CBS; Robert Voets / CBS; Jaimie Trueblood / CBS via Getty Images

Mark Harmon - Behind-the-scenes filming of Sins of the Father episode of NCIS
Monty Brinton / CBS

Harmon (on set in 2011) gives 100 percent on the job—always has. “Whatever I did as an athlete, a student, an actor, I worked at it,” he says. “I love going to work. I believe in putting in the time.”

NCIS - Wide Awake - Mark Harmon and Camryn Grimes
Sonja Flemming / CBS

In Season 17, Gibbs gets a new neighbor, Sarah (Louise Barnes)—and really connects with the single mom’s 9-year-old son (Jack Fisher). “Playing that was fun,” Harmon recalls. “I’ve always thought there is a part of Gibbs that is still a kid.” (Too bad Sarah is also a secret terrorist.)

Pauley Perrette and Mark Harmon - behind the scenes at NCIS
Richard Foreman / CBS

“Abby is the only one who can crack back with him, like ‘Gibbs, you’re being crabby,’” says Pauley Perrette, who played the lab rat from 2003 to 2018. “No one else would be allowed to.” Here, she and Harmon shoot Season 9’s “Restless.”

The NCIS team celebrates their milestone 150th episode with a cake-cutting ceremony. Series regulars Rocky Carroll, David McCallum, Cote de Pablo, Mark Harmon, Sean Murray, Pauley Perrette, Michael Weatherly and special guest star Robert Wagner
Sonja Flemming / CBS

A sweet way to celebrate 150 episodes! From left, in 2009: Rocky Carroll, David McCallum, Cote de Pablo, Harmon, Sean Murray, Perrette, Michael Weatherly and sometime guest star Robert Wagner.

Sonja Flemming / CBS

Gibbs takes action in front of a hotel in the Season 9 premiere, “Nature of the Beast.” (From far left: Matt Craven and Bryan Friday.) Harmon based aspects of the character on real-life NCIS agent Richard Warmack.

Mark Harmon as NCIS Special Agent Leroy Jethro Gibbs, Emily Wickersham as NCIS Special Agent Ellie Bishop
Eddy Chen / CBS

Harmon and Emily Wickersham, aka NCIS Special Agent Ellie Bishop from 2013 to 2021, consult on Season 17’s “In a Nutshell.” Gibbs looked out for Bishop, to the point of destroying one of his all-important rules for her!

Behind the scenes of 'NCIS'
Jaimie Trueblood / CBS via Getty Images

Typical day making an episode (here, Season 9’s“Rekindled”)? “You open the stage door and there’s a train going a thousand miles an hour,” Harmon says. “You just have to grab on.

Cliff Lipson / CBS

Junior Special Agent Tim McGee is at Gibbs’ side for Season 8’s “A Man Walks Into a Bar…”—and nearly 11 years later, he’s the seasoned special agent at Gibbs’ side when he announces he is retiring to Alaska.

NCIS - Mark Harmon as Leroy Jethro Gibbs and Christopher Lloyd as Joe Smith - 'The Arizona'
Michael Yarish / CBS

Christopher Lloyd’s moving appearance as a Pearl Harbor survivor in Season 17’s “The Arizona”—a role written with the Emmy winner in mind—elicits some startlingly personal admissions from Gibbs. “Sometimes someone else opening up about their experience makes it OK for that person to address their feelings,” Harmon says. “Once Gibbs gets to the truth, he doesn’t quit.”

Sonja Flemming / CBS

Per Harmon, Gibbs sees most things “through the crosshairs of a scope.” For real: In Season 18’s “Head of the Snake,” the expert sniper actually shot McGee in the leg to prevent him from approaching a plane that’s about to explode.

Monty Brinton / CBS

It’s hard to look at Harmon or Wagner, who’s logged 13 episodes as Anthony DiNozzo Sr., in Season 9’s “Sins of the Father” against those orange Bullpen walls! The series’ 400th episode in 2020 shows their origin—and the part they played in a crime—back when Gibbs met McCallum’s Donald “Ducky” Mallard decades earlier.

Wilmer Valderrama, Sean Murray, and Gary Cole take a selfie in NCIS
Michael Yarish / CBS

Wilmer Valderrama is all set for a selfie, but it looks like castmates Murray and Gary Cole need a little more time to finish their morning coffee.

Sean Murray as Special Agent Timothy McGee and Cay Ryan Murray as Teagan Fields In NCIS
Michael Yarish / CBS

In Season 19’s “The Brat Pack,” Murray’s McGee forms a bond with Teagan Fields, a teen suspected of breaking into military housing. Their chemistry came naturally: Teagan was played by the actor’s daughter, Cay Ryan Murray.

Wilmer Valderrama kicks back during the filming of NCIS
Robert Voets / CBS

The camera loves Valderrama! He takes a break at Torres’ desk while filming Season 20’s “Head Games,” about a memory-challenged murder suspect.

Rocky Carroll in NCIS
Cliff Lipson / CB

Leon Vance actor Rocky Carroll has stepped behind the camera to direct 22 episodes of NCIS, including “Peacekeeper” in Season 19.

Vanessa Lachey in NCIS
Robert Voets / CBS

NCIS: Hawai‘i star Vanessa Lachey chills on set while shooting the Season 20 crossover “A Family Matter.” A former MTV host and Miss Teen USA, Lachey is the first woman to lead an NCIS series; she also cohosts Netflix’s Love Is Blind with husband Nick Lachey.

Sean Murray, Vanessa Lachey, and Wilmer Valderrama in NCIS
Robert Voets / CBS

Lachey is all smiles with Tennant’s mainland counterparts, despite having to ditch Hawaii for Washington, D.C. Wait, never mind—NCIS is shot in sunny Southern California!

Wilmer Valderrama, Jason Antoon, and Vanessa Lachey in NCIS
Robert Voets / CBS

T’N’T (Tennant and Torres) bookend Jason Antoon, aka intelligence specialist Ernie Malik on Hawai‘i. Did the island cast bring Valderrama a gift, or did Torres nab a souvenir on the previous season’s Oahu visit? The hula dancer actually sits on Jessica Knight’s desk.

Gary Cole in NCIS
Michael Yarish / CBS

The camera may not be on Special Agent Alden Parker during filming of “The Brat Pack,” but Cole is always ready to hop into action.

Brian Dietzen and Katrina Law In NCIS
Robert Voets / CBS

As Jimmy and Jessica work a case for “All or Nothing” in Season 19, Brian Dietzen and Katrina Law refuse to let a little fake blood ruin their time on set together.