Character mistake: When Trish's car stops running, Tommy states that its the solenoid that is the issue. A starter solenoid is responsible for sending voltage to the starter when the ignition is engaged. 1st problem: The car would not stumble and stall because of a faulty solenoid. 2nd problem: The starter was already engaging while Trish was hitting the key. So bridging the solenoid was pointless. The only reason to bridge a solenoid is to create a connection from 12 volt to the starter when the internal system is compromised due to wear. But that wasn't the case because when she was trying to start it, the starter was turning the engine. Plus the solenoid has nothing to due with the way an engine will perform (running, misfiring, not running).
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: Mia's Sea-Monkey, in a vertical position, was shown sinking to the bottom the jar. It isn't clear if the Sea-Monkey was dead or if Mia was referring to it when she said, "She's gonna freeze to death, Aiden", but Mia should have known how to properly care for her Sea-Monkey (or refer to the instructions) and, realizing the room was too cold, should have done something - such as wrapped a towel/blanket around the jar and/or moved the jar to a warmer location (e.g, near the fireplace). (01:22:33)
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: 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: When Chafuka is controlling the zombie Barry with her voodoo doll, he's supposed to be repeating her words so precisely that he even imitates her accent. But when she says "that darn fool paper, it fall on the ground," Barry repeats it as "The darn fool paper fell down to the ground."
Character mistake: When Burt, Ernie and Spider go into the hall after questioning the zombie Burt says his own name instead of Ernie or Spider.
Character mistake: The ref says there's no rules before McClure fights Whiplash but she tries stopping them later.
Character mistake: There are signs out front as the Spenglers arrive at the dirt farm. One of the signs is a call back to a scene in Ghostbusters 1984. In the scene, Ray quotes the book of Revelation: "And I looked, and he opened the sixth seal, and lo, there was a great earthquake. And the sun turned black as sack cloth, and the moon turned blood." When Finn Wolfhard reads it he misquotes the line saying "The sun became as black as cloth."
Character mistake: When the 3 boys and Rogers are trying to recruit scouts, they pledge to Rogers and Carter raises his left hand but in the next shot he has his right hand raised. (00:09:05)
Character mistake: Remy mentions that the insects are part ant, cockroach and termite. She dismisses the mantis side, which allows it to mimic.
Character mistake: When John and Cassie are in the school library and look up about the disease, the book caption reads: "arm amuptation." The word amputation is misspelled.
Character mistake: When Leon goes to see Susan Hoff with his photography portfolio she tells him he needs improvement. After she leaves, Leon tells Jurgis that he thinks she hated his work and Jurgis tells Leon "when she hates somebody's work she gives them about a minute, you got three." In reality, she actually did give him one minute almost to the second. (00:06:58)
Character mistake: A detective (Briggs?) told Sonny, " that I was stupid enough to believe your dark fantasy NINE-ELEVEN call." [emphasis added] An American law enforcement officer, in particular, should know and use "nine-one-one" (911) when referring to the nationwide emergency telephone number. "Nine-eleven" (written 9/11 and NOT 911) is used to refer to the September eleventh (9/11/01) terrorist attacks in the U.S. (01:15:57)
Character mistake: When Chucky is looking up the information about Andy on the computer, the word juvenile is misspelled "juvinile."
Character mistake: Over the phone, Julie told her sister Sara, " I got them [parents] a bouquet", pronouncing the "T" in bouquet. Bouquet has French origin so the "T" is silent. Bouquet is properly pronounced like bow-kay (American English) or boo-kay (British English). (00:00:55)
Character mistake: When Annie is in the red truck, she says that she'll be cooking for ten staff. When Alice goes to the beach, she tells Bill that everyone has arrived except for Annie. Even if she had arrived, there would only be eight of them: Christie, Annie, Ned, Brenda, Jack, Marcy, Bill, and Alice. Two shy of what she told the truck driver.
Character mistake: Zoe states that Lilly's condition is very contagious and will spread through the camp if they don't go out and get the proper medical supplies they need. She puts Lilly in quarantine... and then proceeds to visit Lilly with no protective equipment. No mask, and even touches Lilly with her bare hands before going back out to the rest of the people. (00:19:20)
Character mistake: Roy says, "He thinks the wounds look self inflicted." But the doctor who said that was a female.
Character mistake: Set in Texas, the Sheriff threatens the wrongdoer with the gas chamber. Executions in Texas at that time were all by electrocution, namely by "Old Sparky," the electric chair. Texas has never used the gas chamber for executions.