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Nightmare Fuel: CSI
CSI: Crime Scene Investigation, original flavor, doesn't shy away from gruesome cadavers or their stages of decomposition. However, there are those who take the cake. Liquid Man, a homeless man stuffed into a duffel bag and killed, turned into so much soup by advanced decomposition and the Nevada heat. The bag sloshed when moved, and the man's remains weren't so much cleaned off the coroner's table as flushed down with a hose.
And if that wasn't enough, a later season gave us the Amazing Bloat. You might never look at hot baths the same way.
The rotting juice from that man leaked through the ceiling and filled the entire house, and his decomposing, mouldy body had a brain that looked more like green jello than anything else.
Another victim was left for three days after being stabbed before the police got to the house. The guy was bloated almost beyond recognition and had to be POPPED in order to keep him from bursting inside the van.
The Miniature Killer is far and away the creepiest thing the series has produced thus far.
Really, any of the serials and their methods on the show range from unnerving (Paul Melander, The Strip Strangler, The Blue Paint Killer) to sick (Dr. Jekyll, Gordon Daimer, Nate Haskell) to just plain weird (The Mannekiller, The Miniature Killer). And that's just the original CSI.
Meet Dr Jekyll, your friendly unlicensed surgeon who orders a sophisticated device for brain surgery custom-made, then drugs the guy who made it, DRILLS HIS HEAD OPEN AND PUTS RADIOACTIVE SEEDS INTO HIS BRAIN, makes a wig out of his hair, puts it back, and leaves without a tip. He also specialises in putting an extra appendix in you while you're deeply asleep, and tying your guts into a bowtie through your bellybutton.
Don't forget inserting a device into a victim's artery that will cause it to gradually expand (resulting in increasingly excruciating pain) until it ruptures. Oh yeah, the guy he does this to? His own father.
The recent episode "19 Down" (aka the episode where Lawrence Fishbourne debuts). Specifically, the freak of the week, who looked like Noah Bennent/HRG from Heroes as a serial killer. The way he described what he did to his victims in front of a whole class (albeit via a live feed, not in person) must have rather traumatised the students.
Then there's the opening of the same episode, which gives us a nice time-lapse (with cuts) of a body stuffed into a plastic bag bloating, putrefying, and essentially melting.
The sixth season opener, with two bodies left to decomposemelt in the trunk of a car. And Greg having to grope inside the contents looking for the drain plug... and getting (warning: severe Squick) a mouthful of the liquefied corpse juice for his troubles.
Try that young girl who jumped off the roof in a bikini. Turns out, her hypnotist was responsible for not only indirectly murdering her, but also a series of bank robberies as well. But dear, sweet God, the girl's legs HAD. NO. BONES. They were liquefied upon landing! And seeing all those people in the bus screaming as the girl hits the roof...
"4x4", with the bodybuilder who had that black goo behind or in his eyeballs.
The final part of the sitcom episode. It's all very kooky and staged until the two murderers implicitly reveal that any one who drank from a bottle of vodka laced with anti-coagulant will die in the same manner as the victims of that episode. Cut to one of the sitcom actors shaving, nicking his throat with the blade which causes blood to pour down his neck.
Season Eleven gives us the debut of Squeegel. Brrrrrrrrrr.
Rylan Gauss◊ in "418/427". Incredibly creepy pedophile. No matter how liberal you are, you'll probably be glad when he's killed, even though he's not the perp.
Part one and two of "Grave Danger" where Nick is buried alive in a glass box with only a gun and a tape recorder telling him he's going to die there. And then the air begins to run out and he has to shoot the light with his only bullet to get more time with the fan on. And then some ants start to eat him alive. And then it turns out there are explosives under the box and he must wait to be rescued.
One scene in the second part involves Nick hallucinating that he died within the box, and watches Robbins dissect him laughing all the while. And it's all from Nick's point of view.
* Las Vegas Season 5 Episode 8 "Ch-Ch-Changes"... the discovery of the second body. Full stop.
"Sqweegel," from Season 11 Episode 4. Essentially an unholy combination of Gollum and a contortionist in a Gimp suit... uugggghhhh.
Yeah, it didn't help that he moved like a lizard and at the end said I am no one...
Even worse, Sqweegel is a crossover from the CSI creators book series "Level 26," so we're never going to get any resolution.
What about the episode where the first bit of the victim we find is just a head? A very mangled head at that. And if that wasn't bad enough, we find that the victim died from being buried up to their neck and letting wild dogs kill him...
The sub-plot of the recent episode "Unleashed" was purely this. It involves a beautiful, pregnant teenage cheerleader named Maria, who was two weeks away from giving birth, commit suicide by hanging herself! First it involved a fight with her boyfriend that caused him to leave her. And before that, a viral video of her cheerleading tryouts got leaked as revenge because her boyfriend dumped his former girlfriend (who was the Homecoming Queen) for Maria, and when the bad cheerleaders got suspended, they made the video global and caused Maria to suffer a horrifying Humiliation Conga leading to thousands of hate messages from people she never knew! Between her father's death and her boyfriend dumping her, she felt lonely and hung herself. Plus, right after Nick and Robbins take her unconscious body out of the closet, they have to cut through her belly with a knife. Absolutely brutal, especially if you've been a victim of cyberbullying.
There've been a lot of freaks and psychopaths on the CSI series over the years, but the guy from the season 4 episode "After The Show" has to be one of the creepiest. From the haunting, echoing music played on the cold open and the way he obsessively stares at the victim on TV in the dark, his weird obsession with eyes, the way he stares at Catherine and tries to manipulate her, and his final Villainous Breakdown... yikes.
"Pirates of the Third Reich", especially the surgically conjoined twins scene. Just...*shudder*.
The recent episode "Deep Fried and Minty Fresh" features a guy getting killed by having his head dunked in a deep-fat fryer. Of course, the Necro Cam shows it happen about three times. One sequence details the hot grease entering his trachea, burning it up and causing him to asphyxiate.
"Appendicitement". Waugh. Killer makes a bunch of people humanitarians without their knowledge.
CSI Miami's "Tipping Point". A fellow is Buried Alive in a construction site, and is only discovered when a giant drilling machine breaks through the coffin he's imprisoned in and rips him apart. And of course, said event is repeated over and over again. Only episode I've ever had to turn off and, to this day, have never been able to think about re-watching.
One episode of CSI: Miami had a guy get knocked into a pool, the water of which was replaced some kind of horribly corrosive chemical. We're treated to pretty much a minute straight of the guy thrashing and screaming as the stuff eats away at him, and in the end he looks like one of The Skinless from Hellraiser (and is still sizzling away when the team arrive).
Another episode features a special machine gun that practically liquefies anyone it hits... Gah... just... GAH!
CSI New York
CSI: New York — people getting gassed to death by exhaust fumes in the back of a cab. Knowing that the Nazis did something very similar before switching to Zyklon B makes it worse.
Whoever wrote the last part of the episode where it appears that the much-loved Lindsay Monroe-not-yet-Messer is about to suffer the same fate deserves public castigation.
And so does whoever wrote the secondary plot of the episode "Heroes," wherein Det. Aiden Burn (dismissed early on season 2, after violating the chain of custody of the evidence in a serial rapist case) is brought Back for the Dead as a charred corpse, of all things — killed by the same rapist she was trying to apprehend. The imagery alone is enough to induce more than a few nightmares.
Until they reconstructed her face (which is creepy enough), they were treating her exactly the same as any other body, completely unaware of who she was. Hearing them talk about her in such a clinical way just emphasises the horror when they look at the reconstruction and figure out it was her...
That poor guy whose lower jaw (and most of the face below the eyes for that matter) was blown off by an exploding cigar.
It was almost a relief to know that that's what happened to her — because the episode was entitled "Necrophilia Americana". The title alone gives enough disturbing mental images about the episode's subject. (It's actually the scientific name of the carrion-eating beetles in question.)
"Where There's Smoke", the second ep of season 9. The first victim gets essentially boiled alive in an elevator because a mad arsonist rigged it up to catch fire after she was alone. Then, they show the charred corpse. The next victim gets something added to what he was eating that interacts with the other liquids and stomach acid to literally burn him to death from the inside.
"Blacklist (Featuring Grave Digger)" - episode 2 from season 6 - there's something about the murderer's raspy voice over the phone and on the GPS in the car gives me chills.
In universe for Mac in 'Seth and Apep', when he gets the package with the severed tongue. He can't stop the horrific scenarios in his mind about what they might've done to Christine. He's really relieved when he gets the phone call her kidnappers made her make and hears her voice.