Factual error: With Irv and Blaire, one of them picks up the handful of popcorn and presumably eats the spider. While inside the eater, the spider would bite and poison whoever it was inside. When they find both of them dead, the spider crawls out of one person. Why would it leave one body and actually take the trouble to go inside the other rather than just bite them on the skin like the others? It's not like it would crawl out and back into the bowl to be eaten by the other person.
Suggested correction: We actually don't see either Irv or Blaire "eat" the spider at all. We just see Blaire take a handful of popcorn with the spider inside. Next we see both dead bodies, and then a spider crawls out of Irv's nostril. So the spider could have bitten both people on their skin in short order and then crawled into Irv's body, for whatever reason, after he was already dead. Or, there could be two completely different spiders that killed the pair at around the same time. As the action happens off-screen, it can't be a factual error, we simply don't know exactly what happened.
The whole scene doesn't make sense. The fact that Irv pours the butter on the popcorn with the spider in the bowl, Blaire doesn't feel the spider in her hand when she picks it up with the popcorn, and they are still sitting in the same position watching Wheel of Fortune after being bitten. Only Irv's Coca-Cola can is lying on the floor with some popcorn pieces. The popcorn bowl is still on Blaire's lap, showing they did not have seizures to the spider's venom like the other victims. It also doesn't make sense that the spider doesn't bite Irv when he carries the bowl from the kitchen to the living room.
The mistake entry as written states that the spider is eaten by one person and then eaten by another, with both people dying afterwards. Since we do not actually see that happening, this doesn't count as a Factual Error. The fact that the victims do not seem to have violently seized prior to death should be submitted as a separate entry.
Factual error: Towards the end Ross pours wine on the egg sac to light it. Wine doesn't contain enough alcohol to ignite.
Suggested correction: He uses cognac and not wine, which is why it burns.
Continuity mistake: When Jerry Manley is shown in the coffin his head is on the right side. When they show the shot inside the hole before inserting the poles, his head is on the left.
Other mistake: The wood coffin that Jerry Manley is placed in has no bottom. Right after showing him in the coffin they seal the top, insert handles and somehow carry him off.
Revealing mistake: At the end when the dock 'kicks' the king spider off him into the fire, we hear it scream like a stuck pig. Then additional screams from the 'burning' spiders inside the pulsating nest, and when the doc torches both the king spider afterwards.
Suggested correction: Not sure how this is a mistake. Sure real world spiders don't making squealing noises but real world spiders also don't jump 30 feet or have venom potent enough to kill a human within seconds of being bitten.
It's a mistake because spiders cannot vocalize at all. The film creates a new spider species with exaggerated aspects of real life spiders: extremely potent venom, highly aggressive behavior, jumping ability, etc. What the film can't do is give the spiders traits they couldn't possibly have in real life.
Factual error: The shadow of a spider climbing up the window makes a 'tick'ing sound as it moves, when spiders don't make sounds.
Revealing mistake: When the General is lowering himself towards Jennings on a string of web, there's a couple of shots where the spider is completely immobile, revealing the spider to be a prop. Most noticeable just before Jennings smacks him with a wine bottle.
Revealing mistake: Near the end it is way obvious that the king spider is animatronic as it goes for the doctor, considering it's tech string is quite visible in the closeup. And it "hisses" as it's lowered.
Other mistake: When the exterminator steps on the little spider it makes a loud dramatic 'crunch' and then when he lifts his boot the bottom is overcovered in fake brown goo.
Revealing mistake: Two very different types of spiders are used in most of the shots. In the closeups they are larger, with bulbous legs, defined hairs, and big eyes.
Revealing mistake: When Atherton is using his fog machine to spray up into the tree look to his left, you can see another spray of the fog being added to the tree by an unseen stagehand.
Continuity mistake: It's way obvious that the king spider attacking the doc at the end is animatronic as its appearance changes. In the far shots the legs are wide spread and it's a purplish color. But in the closeups it's black and half the size.
Other mistake: Near the end when the doctor is pursuing the fake king spider moving along inside the pipes, it makes loud, exaggerated tapping sounds, and then "jumps" out at him from the end pipe and attacks.
Visible crew/equipment: Near the end when the doctor and his family are getting attacked by the spider's, half are CGI and the others fake as you can see the Tech wires making them move. Then when he's lying on the floor collecting himself, there's a pulsating sack in the corner, with a fake spider leg sticking out.
Revealing mistake: When Margaret (the blood pressure lady?) gets settled for the night, one of the baby spiders is crawling toward the couch where she's sitting. In the very next shot that same spider is suddenly 'hiding' inside the lampshade above her and bites her.
Continuity mistake: After Becky's dad comes into the bathroom, and she screams, covering herself with the shower curtain, you can see her brother, who had died at the football game considerably earlier in the movie, through the bathroom's doorway, standing in the hall. It's only for a split-second, but as long as you're looking in the right spot, it's very clear.