The early episodes of the series set the course for all kinds of spooky. I mean, the monster eats the pilot in a far more gruesome manner than what would later be canon. Certainly you must've gotten chills when Jack, Kate, and Charlie are visiting the cockpit. And the first time we see a dead person walking around the island (Christian) is very creepy indeed.
As for the pilot's death, it's not contradictory of the later canon at all. He wasn't shown to have been "eaten", just battered and bloody. Smokey could have easily beat him into that state. Still very scary, this troper remembers being horrified when we first saw his body perched in the tree.
Jacob's cabin, for one.
Jacob himself, for two.
Except that wasn't him. We now know it was The Monster. I'd still like to know who the other guy was, though, the guy whose eye we saw.
It was Christian.
Christian (well, MIB in his guise) was confirmed as being the first figure. The second figure was probably either Jacob or another case of MIB projecting himself (like he did when tormenting Eko).
"Teresa falls up the stairs, Teresa falls down the stairs..."
Just about anything to do with the hatch button, although the Swan training film is particularly notable in its creepiness.
The terrifying moment when the countdown ran out and Egyptian symbols started appearing instead of numbers. Add to that the automated voice saying "SYSTEM FAILURE" over and over again, the sound of something metallic smashing repeatedly against the other side of the wall, and that low hum getting louder and louder...
The dynamite at the end of season 1. ** And if that wasn't enough, in season 6 the same damn thing happens again. Apparently Illana's Plot Armor wasn't strong enough to overcome a bag full of dynamite.
After Ben moves the Island several characters begin experiencing "time flashes" which are accompanied by a blinding flash and a increasingly loud noise that sounds like chimes, followed by a whooshing sound and magnetic humming. Hear it here.
Ben is terrifying at times. That creepy unblinking stare of his... *shudders*
"YOU KILLED MY DAUGHTER!" Although it's a CMoA for Ben, it doesn't change the fact that it's absolutely TERRIFYING.
In Season 2, when he was a prisoner: How scary are you when you're tied up in a cell repeatedly getting the crap beaten out of you every other episode, and you can STILL give people nightmares?
"You guys got any milk?"
So Creepy Awesome the production stag decided to make Ben a recurring character. Because he was that scary and awesome.
"THIS PLACE IS DEATH"
After spending the first five seasons being scared to death of the black smoke monster, there's something very unnerving about seeing the island through its eyes as it flies around making that horrible clicking sound.
The look on Un-Locke's face when he sees the little boy. He actually looks scared, which given what he is and what he's capable of is spine chilling.
And for that matter, Un-Locke himself.
The Season 6 episode "Sundown", especially Claire's creepy backwards singing of her old Leitmotif, Catch A Falling Star.
For me it was when Kate found Claire in the hole. Especially Claire's angry Kubrick Stare when Kate told her that it wasn't the temple people who took Aaron. It was really her. Also, Claire happily delivering the following line with a smug smile on her face: "He's coming Kate! He's coming and they can't stop him!"
Also from "Sundown", Sayid's very brief conversation with Ben, complete with slasher smile. When Ben is creeped out, you know something's terribly, terribly wrong. It was also just slightly awesome.
Considering what a creepy, Ax-Crazy guy he is, it was rather unnerving to see Martin Keamy again.. There was something very odd about his eyes — maybe contacts, maybe just lighting — which sent him into the Uncanny Valley. Maybe it's the fact that this particularly evil monster is actually smiling. You know something's wrong when he's cheerful.
But you must admit, he makes great eggs.
The scene where Claire and Sayid, now both completely turned over to the side of evil incarnate, are walking calmly through the carnage left over from the temple attack. With Claire singing a cheerful rendition of 'Catch a Falling Star' in the backround.
Claire's "baby". That she knows it isn't real somehow makes it worse.
Going back to the earlier seasons, in the pilot episode the Losties first get the radio working and hear a transmission in French. After a couple seconds of them cheering that the French are coming to rescue them, Shannon translates the transmission which says in part: "The others are dead. It killed them. It killed them all. It is outside." The Mood Whiplash makes an already creepy moment that much more chilling.
It doesn't help that the counting voice sounds just like a number station (google it, they're creepy).
Fridge Logic says that's probably exactly what the radio broadcast of the numbers was originally set up as.
In the episode "Dr. Linus", even though Ilana forgave Ben and he ultimately didn't have to go through with it, watching him being forced to literally dig his own grave was nothing short of horrific. That's gotta be one of the worst ways to die.
Well, The Candidate provides us with the possible horrors of submarines.
What They Died For, the penultimate episode, gives us the incredibly creepy confrontation between the Un!Locke and Charles Widmore. There are no explicit scares, just an all-encompassing sense of dread that starts as soon as "Locke" arrives, still looking and acting as he has in seasons past, but also...not.
The ending of The End gives us a pretty bad bit of Fridge Horror. So we know Micheal's spirit was trapped on the Island, but there was a chance that maybe it was the power of the Man in Black or the same thing that acted as the source of his power that was keeping Micheal and the other ghosts there. But given that Micheal was absent entirely from the flash-sideway universe, which we find out is like purgatory, this means nothing that happened on the island in The End changed his fate, or that of the other souls trapped in the jungle. Poor Micheal is still trapped on the island, long after his friends have moved on to the afterlife.
And don't think you've got it made even if you make it to the afterlife. You might wind up in a vegetative state there, and thus always be a step away from Heaven, because you can physically do nothing to move on or atone for your sins.And I Must Scream indeed.
There is some hope however, the Ghosts Hugo talked to were the ones who couldn't move on to purgatory yet, because they couldn't let go. And since Hugo and Ben were going to bring Walt back to the island it's probable that Hugo helped him come to terms with what happened and he moved on his own. There are still in fact several other Losties in purgatory who didn't make it to the Church, but some of them are awakened and are most likely going to go meet up with the rest of them when they're ready. But as for guys like Anthony Cooper, there really seems like there's no reprieve, not that I'm complaining.
Locke's strangely horrifying line "You don't have a son, Jack." That's some existential Mindscrewing right there. Since David argued with Jack and didn't act like an imaginary being, it can be assumed he had free will, so when Jack and Juliet left... did he just fade away? Did he die? Is he an orphan now?
At Lostpedia they make the case that David must be real according to their interpretation of Christian's speech. He's just a surrogate. Now who he was in life if they are right in this interpretation, who his parents really were, and what it takes for him to move on, are other questions entirely.
Or perhaps he's sort of junior emissary, not unlike Clarence in It's a Wonderful Life. But yes, it was pretty spooky when Locke said that to Jack, since it's at that moment when what's going on in the "alternate timeline" (HA) really starts to become clear.
It's possible that David is actually the son of Kate and Jack, as speculated by the Tumblr blog called "Lostanswers". He has freckles like Kate, similar in appearance to Jack, and there is a likely point in Season 5 or 6 where he was concieved.
Claire's nightmare from Season 1, especially Locke's eyes.
The scene in which it's confirmed that Ethan Rom wasn't actually one of the plane crash survivors. Going straight from discovering his name wasn't on the manifest and realizing you have no idea who or what he really is to seeing him standing over the alone, defenseless Claire gave me nightmares for weeks.
That oh so very creepy smile he gave Claire and Charlie in that scene should send chills of terror up and down your spine whenever you see William Mapother, regardless of the context.
The accompanying slide trombone sound effect makes it even more eerie.
The season 2 episode when Sayid is interrogating "Henry Gale": "My name is Sayid Jarrah, and I am a torturer." The creepy music and Naveen Andrew's emotionless delivery makes it absolutely chilling, coupled with sudden look of Oh Crap on Ben's face as he realizes Sayid isn't bluffing...
Fridge Logic adds another layer. Ben knows exactly who Sayid is, and should have known what he's capable of. The fact Ben is scared means Ben made a conscious decision about what risk Sayid posed to him at this point, and has just realized he made the wrong call.
On a "List of Things You Don't Want to Hear When You're Tied Up and Locked in a Room Alone With Another Person," this ranks pretty high...
"I don't know what is more disquieting: the fact that the rest of the statue is missing, or that it has four toes."
The episode where Michael, Jin, and Sawyer are told by the Tailies that 23 people survived in their section, get taken to their hideout, and find only five:
Michael: I though you said there were 23 of you.
"Did you just call that... thing?!"
One episode ended immediately after Michael shot Ana Lucia and Libby. Wham.
Room 23. Watching Karl being strapped to a chair, drugged, and forced to watch a bizarre video with loud music blaring in his ears and weird clips of seemingly random images are seen flashing on the screen (one of the images consists of several, creepy doll faces) is disturbing.