- Unlike the rest of the series, this movie is considerably a lot darker and has plenty of horror elements. There's Dennis, the seriously threatening thugs, the brainwashing bucket helmets, the skull infested area, the horrible looking monsters, the trench, the diver, and the climax involving drying up and turning into non-anthropomorphic animals in a gift shop. Worse than all of that, ALL HAIL PLANKTON!!!
- The activation of the bucket helmets.
- If you listen closely to the score, you can hear the fluttering woodwinds making a creepy-crawly sound to accompany all the helmets turning on.
- Plankton going Not-So-Harmless Villain (to the point of pretty much crossing the Moral Event Horizon) is terrifying as well considering how he usually is.
- Mr. Lawrences performance as Plankton during this scene also deserves a mention; throughout the beginning of the film, hes prone to yelling more than he ever did in the show. When he has Squidward captured, he screams Who can stop me now?! WHO?! with full blown madness and laughs madly, a direct contrast to his usual hehehehehehe laugh. It's unnerving, to say the least.
- The way the sequence switches from color to a long-shadowed sepia tone a 'la Triumph of the Will. Let that sink in for a second.
- Then he does it to King Neptune.
- The first fish whose helmet is destroyed happily declares "I'm free!" which implies that the bucket helmets keep the victim perfectly aware.
- We can see babies wearing the helmets. Think about that.
- The old lady at the ice cream stand, who turns out to be some kind of giant monstrous frogfish.
- The GIGANTIC deep-sea eel that swallows the anglerfish and the Patty Wagon. It's so monstrous and quite spooky-looking, and the way it's animated to move so slowly really sells it's intimidating mass. Those surprised faces Spongebob and Patrick make are completely justified.
- Frozen Mr. Krabs. The worst part is that he is still completely conscious. The whole reason why he is frozen in the first place is for committing a crime he didn't even do and has only six days before he's put to death by fire.
- His face is frozen in a permanent scream, too.
- Dennis. Enough said. He's a pretty terrifying villain for a kids movie.Plankton: HE'S A VICIOUS, COLD-BLOODED PREDATOR!
- One of his creepier moments is when he casually rips the lips off of the hillbilly brothers after they laughed at him over a stupid joke they made up on the spot and later on punching a thug to his death. These scenes really establish how Dennis is not one to take nonsense of any kind unlike the rest of the funny characters.
- He gets even scarier in his last moment when he is having his Villainous Breakdown and yelling at Spongebob and Patrick about how he is "through messing around" with them. It doesn't help that his eyes are all red, swelled and watering from irritation as he glares down at them.
- (Slasher Smile) "Did you miss me?"
- Shell City, once you see it from SpongeBob's perspective. Just imagine being trapped inside a room with no way out with hundreds of dead people surrounding you.
- Not just dead people, dead people dressed up to be sold like gifts.
- King Neptune's facial expressions can get really freaky at times when he gets really pissed.
- The close-up on Plankton's face as he gives his third and final "YES!!!" when Neptune is about to immolate Krabs. His eye is crazed and widened and he's got a huge Slasher Smile on his face, complete with fangs for whatever reason.
- "ALL HAIL PLANKTON! ALL HAIL PLANKTON! ALL HAIL PLANKTON!"
- The Cyclops. Mindy specifically warns the heroes about a giant cyclops guarding Shell City, and that if he catches them, they will never be seen again. Then they finally encounter the dreaded Cyclops, which turns out to be a realistic deep sea diver with a glowing green viewpoint. From Spongebob and Patrick's perspective, the Cyclops looks downright unnatural compared to what they have seen so far, and it is utterly massive, accidentally crushing the nightmarish hitman Dennis with his boot. As the Cyclops quickly captures Spongebob and Patrick, he brings them up close to his glowing, expressionless "eye," silently watching them scream in terror, before taking them away to Shell City. Unlike most monsters in the sea, the Cyclops seems to enjoy watching sea creatures get scared, laughing maniacally before slowly killing them and turning them into gifts. And then he leaves Spongebob and Patrick to dry up under a hot lamp...
- The fact that Mindy knows about the Cyclops guarding Shell City is probably the reason why no one has returned, it makes King Neptune's utter despair that the crown is stuck in Shell City seem much worse; its possible that King Neptune is afraid of the Cyclops, or at least unwilling to challenge him, even to get back his crown.
- What makes him really disturbing is that whenever actual humans are used as villains in Funny Animal cartoons, they're usually Obliviously Evil, or at most, an Egomaniac Hunter. It's heavily implied that the Cyclops, whoeever he really is, is perfectly aware that the sea creatures he's been tormenting and selling are sentient, and that he enjoys their pain and fear. He's easily a hundred times the size of the fish and marine life he tortures and there's nothing they can do to stop him. He even wears his diving suit inside his shop, even though there's no reason to other than enforcing his dominance over his victims. It's especially callous considering that he runs a souvenir store and even the most callous normal human would be disgusted at his sadism and cruelty.
- The main thug trying to weed out the "Bubble-blowin' baby". It starts off rather silly, but as Patrick and Spongebob actively try not to sing along to the "Goofy Goober" song, they start to melt, foam at the mouth and to top it off, they have pain-contorted faces.
Nightmare Fuel / The SpongeBob SquarePants Movie