These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Kyle Boone from season 3's episode "Mind Games" was a Serial Killer who mainly targeted women. When Kyle was twelve years old, he murdered his mother and later devoted himself to starting a career in killing women. He would torture them to death, carved a heart shape in their backs, and would often take their tongues as trophies. When he was finally sentenced to be executed by the electric chair, Boone attempted to stay his execution and formulated a plan that involved setting up his lawyer Adam O'Neill as a copycat killer; Adam then kidnapped Agent Cassidy and attempted to torture her to death, though he failed. Boone was also convinced to take the families of his victims to the sites where their loved ones were disposed of. He took them all the way to a Virginia farm, only to dampen their hopes by showing that there was nothing in the barn other than the severed tongues of his victims.
The season 3 episode "Bait" features two goons of Colombian drug lord Carlos Mendez. Eighteen years in the past Angela Meyers testified against Mendez, and then faked her death while she was out sailing. The goons go to the high school her son Kody attended to strap a bomb to his body with the intention of drawing Angela out and killing her along with him and his classmates. This would ensure that the authorities thought that Kody was to blame while Mendez got off Scot-free.
Counterpart Comparison: Shown in the S2 Ep12 episode "Doppelgänger", with the team working with civilian law enforcement, which are all extremely similar to the characters.
Critical Research Failure: In "Anonymous was a Woman", Lieutenant Gorman mentions the presence of UN peacekeeping forces in Afghanistan, which is not true entirely since ISAF is the only international force that provides peacekeeping to help Afghan police/soldiers in securing the country.
After conjecturing that a computer has a twelve-core processor by glancing at its monitor, a character is described as having the "the high score in virtually every massively multiplayer online role-playing game", a feat that would be unachievable in a human lifetime if most MMORP Gs even had high score tables.
The entire plot of "Semper Fortis" proceeds from a Critical Research Failure. A former Navy Hospital Corpsman is arrested (and charged) for practicing medicine without a license. The team laments how No Good Deed Goes Unpunished and how wrong it is. The thing is, it is wrong. Besides being a long-standing principle of common law, most states have some form of "Good Samaritan Law" that offers protection to people who render aid in emergencies. Virginia (where the episode takes place) has Code § 8.01-225 specifically protects "Any person who in good faith, renders emergency care or assistance, without compensation, to any ill or injured person at the scene of an accident, fire, or any life-threatening emergency". Not only would the Corpsman not be charged, she would be even more protected. Her record would ensure that the idiot that arrested her would be tossed out on his ear.
Memetic Badass though he may be, Gibbs can definitely be seen as this, given his occasional penchant for assholish behavior, bending or even breaking the very laws he's supposed to be enforcing, and utter hypocrisy in how he interacts with agents/officers from outside the team who're working on the same case. The series has shown that he could be running NCIS, if he had more patience for the politics.
Anthony Dinozzo can be seen as this too, with actions that are pretty much sexual harassment towards women and his treatment of computer tech McGee which are very much like those of a bully (such as constant insults, cruel pranks, and even convincing most of the women in the NCIS headquarters McGee was gay). He also has the same lack of regard for laws and hypocrisy toward agents/officers outside the team as Gibbs. It's all but outright stated that he's being groomed as Gibbs' successor.
Ear Worm: It seems like such a simple little Theme Tune, but just try getting it out of your head.
People who dislike and/or outright hate every other character on the show will still love Ducky. But hey, it is Ilya Kuryakin...
CGIS Agent Abigail Borin, played by Diane Neal, has a popularity with the fanbase all out of proportion to the number of times she has actually been on the show, to the point where many are clamoring for her to join full time (and indeed, in season 11 a door was cracked open which could potentially allow her to do just that).
Gotta Ship Em All: Gibbs, Tony, Ziva, McGee, Kate, Abby, and, to a lesser extent, Jenny, are each shipped with all the others by fans. The Ziva/Kate ship is particularly jarring, considering Ziva didn't even come on the show until after Kate had died. This leaves only Ducky, Palmer, and Vance who aren't commonly shipped with anyone (though you do occasionally see Ducky/Gibbs or Palmer/someone), perhaps because Ducky is about thirty-five years older than almost everyone else, Palmer doesn't have a substantial amount of interaction with anyone other than Ducky, and Vance was married until very recently.
In one episode, Gibbs is "shot" as part of a sting. In the season 5 finale, killing Jenny Shepard offscreen. Subverted, as they darn well would. She takes four baddies with her, though. And the serial killer's plan to get himself shot and ruin Gibbs' life...it fails. Badly. "Requiem" opens with Gibbs having apparently drowned.
Like you would really blow up Gibbs, Abby, Tony, Ziva AND McGee, and give Ducky a heart attack at the news. Yep, that's the season nine cliffhanger note all the actors have had their contracts renewed...
Like you would really kill Tony and Ziva off in a car crash 3 episodes before the end of season 10.
Magnificent Bastard: Ari starts off as one of these (shooting Gerald and managing to escape), then does a Heel-Face Turnwhen he saves Presidents Bush and Sharon, then turns into a Complete Monster in his final appearance when he murders Kate and tries to kill Abby.
Misblamed: There's an infamous scene where Abby and McGee try to type on the same keyboard to try and out-code a hacker. What Cracked left out is that they're clearly panicking and not thinking straight, it doesn't work, and Gibbs just unplugs the computer and looks at them like they're idiots, while they look embarrassed about how dumb they were being.
Ari shoots Kate and tries to shoot Abby to deliberately cause Gibbs grief, despite the fact that he could have easily shot Gibbs instead at the time and Gibbs was a more tactically valuable target.
Ari belives that the missile strike that killed his mother was ordered by Eli David, in order to "harden" him into a better killer. Keep in mind that Ari was a child at the time, and Eli was his father. If that wasn't enough, he orders his daughter Ziva to kill Ari, her half-brother, after Ari proves to be disloyal.
More Popular Spin-off: NCIS has far outstripped its parent show JAG, to the point that many viewers haven't even heard of the latter.
The climax of the Christmas EpisodeNewborn King. A pregnant Marine is giving birth while Ziva holds off the mercenaries who are trying to kidnap the baby...but all dialogue and sound effects are muted, with the soundtrack playing "Silent Night." Painfully overdone.
In the episode "Dead Reckoning," an international crime lord is played by some guy you've probably never heard of before. Meanwhile, the timid accountant who turns informer against him is played by Emmy Award winner Christian Clemenson. If you guessed just by reading that sentence that Clemenson is, in fact, The Man Behind the Man, you win a cookie.
Nightmare Fuel: The second-to-last episode of Season 4 has a patient at Jeanne's hospital who died from a heroin bag rupturing inside him - he was a drug mule. His junkie sister and her boyfriend (who ran the drug op in the first place) show up to get the drugs before they're found. Near the end of the episode, the girl snorts heroin FROM HER DEAD BROTHERS INTESTINE. Drugs mess you up, kids.
In "Oil&Water" Agent Borin gives an extremely unnerving and graphic description of what it's like to be blown up.
And Enfant Terrible Rachel Barnes in "Parental Guidance Suggested" - very creepy.
The Problem with Licensed Games: The video game wasn't very well received. For starters only one voice actor from the actual show was in it, it was near impossible to lose, simple plots, poor visuals, etc.
Replacement Scrappy: Averted with Ziva, as she is far more popular and liked than Kate. Viewers who often get introduced into the show from the third season on often don't know who Kate is until they either stumble across an episode where she's mentioned or view one of the first two seasons later on.
Rescued from the Scrappy Heap: Director Vance wasn't well liked until it was revealed there's more to him than meets the eye, and he very likely isn't Vance at all.
After she was poorly received for being overly quirky in Season 11, Season 12 cast Eleanor Bishop as a probie taken under Di Nozzo's wing and attitudes towards her improved as well.
"Angel of Death". A drug dealer and his addict girlfriend try to retrieve the body of a mule, who had the package burst inside him. While the stand-off happens, the addict gets on the table and begins snorting straight out of the opened corpse. Bonus Squick for the corpse in question being her brother!
The exploding bodies in the crypts in "Skeletons."
Some of the dead bodies, before and/or during the autopsy scenes, obviously count. Those makeup artists have no shortage of fake blood and guts.
The flashback of Gibbs' family in "Requiem", and his memories of them in "Hiatus".
The ending of the season 4 episode "Iceman", where even though Mike Frank's son (which he didn't know he had until a couple of years ago) is dead and he's lost so much, he managed to save his daughter-in-law and his granddaughter.
Abby's confrontation with Gibbs in the S7 episode "Borderland" after the cold case she worked on in Mexico turned out to be the man who murdered Gibbs' family and Gibbs subsequently killed.
The whole episode "Friends and Lovers".
"Grace Period", the whole damn thing.
"Better Angels": Jack Gibbs needs his son to meet Walter, the pilot who saved his life in World War II, before he (Walter) dies. The reason? Walter was German (Jack: "I thought I mentioned that" Gibbs: "NO" Jack: "Well, it's not important" Gibbs (who wanted to find Walter with US military records): "It kind of IS") and now that he's dying he's haunted by all the people he killed "for ideas that weren't his". Jack wants Walter to know he's a good man and his son is the proof: If Walter hadn't rescued Jack, his son wouldn't have been born and we all know that Gibbs is a very, very good man (and now Gibbs knows too).
That a German pilot would save an enemy in trouble is old news to Crackedreaders.
Too Dumb to Live: Rivkin. Being told to leave the country thrice, and doesn't get the message. Resisting arrest doesn't make it better.
Unintentionally Unsympathetic: Eli David. Every so often the writers make him look like he is misunderstood, that he is some sort of a ultra-dedicated patriot, and therefore Ziva should try to make amends with him. All these ring hollow, however, because Ziva herself has once explicitly stated that, after abandoning her to death in Somalia, for all intents and purposes, Eli is dead to her.