Gibbs: Cause of death?

Ducky: Well, it wasn't the arrow.

Facts sourced from Wikipedia and IMDB.

1/30. NCIS is set in Washington DC area but is really filmed in Santa Clarita, CA. The Washington Navy Yard is a considerable distance from the beautiful famous buildings in DC: the set decorators chose to put the false, but pretty view to be the one that people see from the squadroom 'window' instead of the Navy Yard's real view, which is much less spectacular.

2/30. Donald Bellisario was in the U.S. Marine Corps as a Gunnery Sgt. The Marine Corps ethos and knowledge of how the Marines work is from real life experience.

3/30. Mark Harmon has been known to wear shirts which have been sent to him by his fans, so that he has authentically old Marine Corps and NIS/NCIS shirts to lounge about in at 'home'.

4/30. Sasha stopped acting on "NCIS" because she didn't realize the amount of physical work related with the show--or, as Bellisario put it, she had never been in a hit show before, so she never realized that you have to keep working day after day, year after year, and, with Bellisario in control, 16 hours per day.

5/30. DiNozzo's wealthy father cut him off from his inheritance when he was 12 years old. Michael Weatherly's father cut him off from his inheritance when he decided to pursue acting.

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6/30. Pauley Perrette, who plays Abby, actually graduated from college with a degree in Forensics, and then moved to New York to get her master's, and it was there that she got in to acting, before coming to NCIS. Producers have said that most of the personality and interests displayed by Abby come from Perrette just playing herself.

7/30. The hand tools that Mark Harmon uses on the set of NCIS are mostly his own. Those are the tools that he uses in his own personal workshop.

8/30. Whenever we see flashbacks featuring young Gibbs, the younger version is played by Mark Harmon's son, Sean.

9/30. There is a picture of Donald P. Bellisario hanging on the "NCIS Most Wanted Wall".

10/30. The sound heard at the beginning and end of each act, when the scene goes to black and white is Donald P. Bellisario making that noise into a microphone. He wanted a unique way of bookending each act and took a microphone and went into a studio and made that sound into the microphone.

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11/30. In 2005, Mark Harmon requested that nobody make any fuss about his September 2nd birthday. New cast member Lauren Holly had other ideas. The frequent victim of Harmon's practical jokes, she collaborated with Michael Weatherly on a Harmon birthday extravaganza. First they ordered 150 t-shirts that read 'It's Mark Harmon's birthday', that were passed out to the entire crew. On Thursday, September 1st, she waited in her hotel room for the heads-up call from Weatherly that shooting was wrapping. At three o'clock a.m., still in her pyjamas, Holly got the call, loaded up her car with party supplies and drove back to the show's sets in Santa Clarita. She and Weatherly then proceeded to cover Harmon's trailer with crepe paper, helium balloons and piatas, then dumped large amounts of confetti everywhere. They decorated every wall, truck and trailer, then, with the cooperation of the art department, put up a picture of Harmon on all the plasma-screen displays in the squad-room set. Holly then hopped on a plane on Friday to fly back to her husband and three sons in Chicago and waited for word on Harmon's reaction. When Harmon arrived to work he saw everyone in identical t-shirts, holding signs, and assumed there was a strike. Weatherly was called by the nervous producers, who were worried what Mark would think. Michael replied "I'm not going to name any names. Lauren Holly". Harmon was very touched by the gesture, which was filmed so he could take the DVD home to his wife. He did however tell Lauren with a grin, "Payback's a bitch".

12/30. Michael Weatherly once stated this when rumors that Mark Harmon was leaving NCIS, "He's the spine of the show. Without him it's a show about jellyfish. We need our spine."

13/30. There are two types of NCIS special agents: full time agents wear a gold badge, part time agents wear a silver badge.

14/30. On the set of NCIS Mark Harmon uses a 1972 Airstream he restored himself.

15/30. Lauren Holly originally auditioned for the part of Kate.

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16/30. Donald P. Bellisario was not sure whether Mark Harmon would be right for the role of Gibbs. However, following his role as Agent Simon Donovan on The West Wing (1999), he eventually decided to cast him.

17/30. At one point, Michael Weatherly's character states "I've got a better chance of hooking up with Jessica Alba than these guys do of infiltrating SeaLift". Michael Weatherly was engaged for a time to Jessica Alba and starred opposite her on Dark Angel (2000).

18/30. In "Enemy On The Hill" Abby is seen holding a locket of her adoptive mother. The photo is Pauley Perrette's real mother, Donna Bell.

19/30. Mark Harmon, who was born in 1951, would be old enough to be a Vietnam era veteran, but his character of Gibbs stated that he was a Gulf War veteran as he was too young to be a Vietnam vet, so Gibbs is much younger than Harmon.

20/30. In the opening credits of the first couple seasons, an aircraft carrier is seen going under the Golden Gate Bridge. This is a clip from the opening credits of The Presidio (1988), starring Mark Harmon as a San Francisco police inspector investigating a murder on the Presidio army base in San Francisco.

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21/30. Donald P. Bellisario named the character Leroy Jethro after his family. His brother's name is Leroy and his father's middle name is Jethro.

22/30. NCIS is one of very few spin-offs to run longer than the original show.

23/30. Mark Harmon received a call during the summer between seasons 3 and 4 telling him to stop shaving - because Gibbs was to have a scruffier look, along with a mustache.

24/30. During one episode, Gibbs was trying to solve a crossword puzzle. As his character is rarely in step with pop culture, he asked DiNozzo for a TV drama with eight letters. Tony answers St. Elsewhere (1982), which has more than eight. Mark Harmon played Dr. Bobby Caldwell on that show from 1983 to 1986.

25/30. The Dodge Chargers used by these Navy Department agents are a color called Deep Water Blue, a special color costing several hundred dollars more than a standard black or white car, which a federal agency would most likely choose.

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26/30. Dell sponsors all the laptops and PCs shown in every season.

27/30. The title of McGee's novel "Deep Six" is the name of an actual novel written by Clive Cussler.

28/30. "FLETC" (flet c) is often referred to in regard to trainees. The word is an acronym for the Federal Law Enforcement Training Center. NCIS, along with 82 other federal agencies, train recruits at FLETC-Glynco, just north of Brunswick, Georgia.

29/30. Timothy McGee uses the pseudonym Thom E Gemcity for his novel 'Deep Six'. Thom E Gemcity is an anagram for Timothy McGee.

30/30. In numerous episodes someone is told to "watch your 6". During World War II pilots would call-out the positions of enemy airplanes by referring to their bearings via the use of a pretend clock face. Twelve o'clock meant the enemy was directly ahead, whereas 6 o'clock would mean directly behind. Basically this means "watch your tail". Another comment "I've got your 6" means "I've got your back".

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