Chances are you don’t know everything that occurred while the cameras were rolling.

Now in its 20th season, NCIS is one of the longest running and most beloved drama series of all time. The series, created by Donald P. Bellisario and Don McGill, tells the story of a team of special agents that work for the Naval Criminal Investigative Service. The group of agents investigate anything criminal that takes place involving the U.S. Navy, U.S. Marine Corps, and their family members, and is set in the United States capital, Washington, D.C..

After two decades on the air, it’s safe to say there have been as many stories that have taken place off camera as on. From casting to production, and everything in between, you won’t believe all of these little-known tales that happened while filming the show.

1

Cote de Pablo Studied Hebrew Specifically for Her Role

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Known for her role as Mossad special agent Ziva David, Chilean-American actress Cote de Pablo studied Hebrew with a language coach to ensure she pronounced all of the words in her character’s native language properly.

2

Sasha Alexander Asked to Be Written Off the Series

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Audiences were left stunned when Sasha Alexander’s character, Caitlin Todd, was killed after two seasons. But the truth is that the actress requested her own departure citing exhausting hours and a heavy workload.

3

Mark Harmon’s NCIS Trailer Was Made From the Shell of an Airstream

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The lead NCIS actor is nothing if not original! Harmon enlisted the help of some crew members to renovate the 1972 Airstream, turning it into a fully functional – not to mention one-of-a-kind – dressing room.

4

Jennifer Aniston Almost Played Agent Catherine Todd

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As Friends came to an end and Aniston was seeking new opportunities, the role of Agent Caitlin Todd on NCIS piqued her interest. The role ultimately went to Sasha Alexander due to scheduling conflicts.

5

The Series Is Filmed Far From Washington D.C.

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Even though the show is set in the United States capital, it’s actually filmed in Santa Clarita, California. Thanks to the hardworking crew, viewers can hardly tell the difference.

6

Rocky Carroll Was the Show’s First Black Director

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Not only was Rocky Carroll’s character of Leon Vance the series’ first Black director, but he remains its longest-running director on the NCIS team.

7

The Show Was Initially Meant to Be a JAG Spinoff

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In its early stages, the concept of NCIS was meant to be a spin-off of the popular series, JAG, which ended its run in 2005. NCIS was ultimately a series all its own, and has subsequently paved the way for a number of spin-offs.

8

NCIS Wasn’t Always the Show’s Name

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The original title of NCIS was a little bit more of a mouthful: “NCIS: Naval Criminal Investigative Service.” It was later shortened to “Navy NCIS,” then to NCIS, as we know it today.

9

Pauley Perrette Studied Criminal Science

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Before she embarked on her long and successful career as an actor, Pauley Perrette, who plays NCIS’ beloved Abby, studied criminal science. She even considered a career using her graduate degree professionally before landing the role that made her a household name.

10

John Corbett Almost Starred in an NCIS Spinoff

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The Northern Exposure and Sex and the City actor almost helped expand the NCIS franchise with a spinoff called “NCIS: Red.” Sadly, it wasn’t picked up and after the pilot, no further episodes were produced.

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11

Creator Donald P. Bellisario Was a Fixture on the Show’s Most Wanted Wall

Though only hardcore fans have likely spotted it, series creator Donald P. Bellasario’s picture was featured on the wall of most wanted criminals.

12

Mark Harmon’s Tools on the Show Were His Own

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Mark Harmon made life a little easier for the prop department by bringing his own hand tools to set for use as props. Not unlike his character, Harmon is a woodworker and was more than prepared for the role