Character mistake: When Chucky is looking up the information about Andy on the computer, the word juvenile is misspelled "juvinile."
Character mistake: When the FBI agent (James Arness) is introduced to the chief the chief asks his if Ed has brought him up to date. The cop's name is Ben, Ed is the one who was killed.
Character mistake: Early in the film we are repeatedly shown the alien character flirting happily with various men, relaxed, confident, even socially forward, in fact often more articulate and socially at ease than the various Glaswegians she encounters. Yet later on, inexplicably, all this social nous mysteriously disappears and she is completely baffled and blindsided by the simplest of social interactions, almost a mute. Since the film has virtually no plot it's hard to see why this jarring turnaround should be so.
Character mistake: The very advanced computer on the plane can't spell, since it infers probabilities that a member of the crew has been "INFECTETED" by the creature. (01:06:40)
Character mistake: During the surgery, one of the surgeons says to give the patient 25 cc's of cyatril. Then one says make it 35 cc's. 35 cc's (or 35 mL) is a full large syringe. The other doctor uses what looks like a 3 mL syringe and it's only partly filled. It seems the surgeons wanted 0.35 cc's.
Character mistake: John would have no reason to ask the CT technician if she had any results. He says "that was a long one," indicating he's had this done before and should know it typically takes around 24-48 hours to get results. (Likely just a line of dialogue added for the benefit of the audience, who may not know.)
Character mistake: When the second fog bank rolls in, the weatherman says it is coming from the south-east, and the DJ says the same thing once; the second time, however, she says the south-west.
Character mistake: It doesn't occur to our heroes (admittedly kids) that you don't need to understand German at all in order to read it out loud. It's arguably easier to read than English! The only inscrutable letter would be "ẞ" but Scary German Guy's right there for help. (True, this is essentially what they end up doing in the end, but they still come about it through a "you don't need to be of age to be a virgin" realization rather than the even simpler "you don't need to know German.").
Character mistake: The ref says there's no rules before McClure fights Whiplash but she tries stopping them later.
Character mistake: At the hospital, the inspector manages to get from the nurse the file of the patient with the liver condition. Forgetting the fact that the Turin, Italy hospital is using English for its documents (it's simply a cinematic convention), the problem is that the letterhead of this document says "Department of Chronic Deseases", misspelling the word.
Character mistake: In the scene where Maggie tells her sister she is pregnant and how far along she is in her pregnancy, her sister says the child will be a Gemini, just like Einstein. Einstein's birthdate is March 14th, making him a Pisces. Lisa also mentions that Shirley Manson from the band Garbage is also a Gemini, when in fact she is a Virgo.
Character mistake: Marjorie's supervisor said the police found Nathan "torturing an animal [dog], there was a struggle and he assaulted one of them." Marjorie then asked, "Is he violent?" Her supervisor replied, "I have no reason to believe so. I mean, he did resist arrest, but that's probably out of fear" and the mental health team said there was "no obvious psychopathy." Social workers/mental health teams should have assessed cruelty to animals and resisting arrest as indicators of potential for violence. (00:03:55 - 00:04:30)
Character mistake: Near the end while in the caves Maggie is the first to go missing, but they use the name Gwen multiple times, the actress' actual name.
Suggested correction: Maggie Q is the actress and she plays the character Gwen Olsen.
Character mistake: The prosecuting attorney told William, "In the interests of getting this thug [Danny] off the streets as soon as possible, his attorney has agreed to plead guilty to assaulting an officer, possession with the intent to distribute, and resisting arrest, and that's all in addition to his parole violations. We're looking at five to seven [years in prison]." The parole violations alone are sufficient to get Danny off the streets immediately. (00:09:34)
Character mistake: The Sheriff calls for Drayton Sawyer to bring out his son Jed (Leather Face) in the movie's opening scene. But it's long been established that they're brothers.
Suggested correction: This is meant to be a direct sequel to the original film, and ignores the other sequels. And if memory serves correctly, the first movie never made any mention of them being brothers. (I just checked and the Texas Chainsaw fandom Wiki backs this up - the original film makes no reference to them being brothers.) So therefore, it is not a mistake if this movie re-writes him as being Leatherface's father.
Character mistake: The Captain of the USS Fragasso comes onto the bridge. A Petty Officer says, "Officer on deck," and salutes while looking out the forward windscreen. He should have said, "Captain on the bridge" and not saluted.
Character mistake: Henderson asks the guy as he's leaving the room to get him some bourbon. They already drank in the bar and spat it out when they found out that everything had turned to blood, so it would still be blood.
Character mistake: Alice shoots the henchmen, the black officer is attempting pull a gun from his shoe but in closeup his leg is white, then back. (01:06:25)
Character mistake: When Inspector Owen calls the village police station the call is answered by a sergeant but at the end of the call Inspector Owen refers to him as Inspector. (00:10:00 - 00:11:00)
Character mistake: Nolan said, "Everybody knows that no sharks swim in freshwater" and Spencer said, "They don't come into freshwater", but there are freshwater sharks (e.g, river sharks) and bull sharks (not true freshwater sharks) can survive in saltwater or freshwater. Jacob Harper (National Aquarium) pointed out eyewitness accounts of sharks swimming up the Mississippi River and "bull sharks have kidneys that recycle salt" but did not mention the glands near their tails that help keep salt in their bodies. (00:08:08 - 00:29:50)