Revealing mistake: When the scientists inject the mouse with poison, they put it in a jar. The, after they place it down you can see someone's hand swap the jar for one containing a dead mouse. You can even hear it. (01:17:58)
Revealing mistake: When Becky sees the spider in the shower, there are two instances when you can see the bodystocking she's wearing, covering her breasts, to preserve her modesty, most noticeable when she screams. (01:11:53)
Revealing mistake: When Jerry Manley gets bitten by the spider in the tent in South America, the others come to look at his corpse, you can see clearly see his neck pulsating, when he should be dead. (00:15:35)
Revealing mistake: When Becky gets out of the shower naked, her father walks in on her and you can clearly see her wearing pants, reflected in the mirror, to keep her modesty. (01:10:05)
Revealing mistake: In the scene where Dr. Ross Jennings is trapped in the corner of the cellar, you can see that the tarantula which starts climbing up his leg has a huge black stick stuck to the back of its body, pushing it along. (01:36:05)
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' spider's inside the pulsating nest, and when the doc torches both the king spider afterwards.
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.
Revealing mistake: Toward the end when the doctor climbs up and throws the alcohol on the pulsating egg sack to torch it, the fake king spider suddenly "pops' up on its hind legs, like a Halloween special effect.
Suggested correction: Spiders can stand on their hind legs in real life, so this isn't a mistake.
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.
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.
Revealing mistake: Two very different types of spiders used in most of the shots. The ones in closeups are larger with bulbous legs, defined hairs, and big eyes.
