Character mistake: During the scene at the office of the University of Oxford, the Union Jack is hanged the opposite way from the proper position. (01:23:10)
Character mistake: Oh claims to not understand the word "my" when he is with Tip and always refers to her mom as "mymom" and "your mymom." But he seemed to understand the meaning of the word perfectly before because he talks about "my best friend Kyle" in his evite.
Character mistake: When Brenda first witnesses Connor and the Kurgan fight, Kurgan says "I am the only one." Afterwards, Brenda asks "What does he mean by there can be only one?" She somehow misheard Kurgan and thought he said the movie's iconic catch phrase.
Suggested correction: This is incorrect. He does say "There can be only one." He's saying it while beating Conner, so the first part is a little muddled and he emphasizes "one", but he does say the line.
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 Joan is searching the web looking for information on what monkeys eat, there is a section on the screen that reads "The diet of monkeys varies form fruits, leaves." Obviously the correct word for this sentence should be "from" not "form." (00:36:21)
Character mistake: According to her biography found in the library, Elise was born November 11, 1885, but William Robinson tells Richard that he met Elise when she was 16 years old, in March, 1903, at which time she would have been 17.
Character mistake: Tom states that the Republic of China released fifteen American POWs in 1955. The People's Republic of China (Communist China) might have done so, but the Republic of China (Taiwan) has always been an American ally and would not have been holding any Americans prisoner to begin with.
Character mistake: Big Ben is loaded feet first into the ambulance, he should've been loaded head first.
Character mistake: During the movie the cat Winky is referred to as male, but much later in the movie is referred to as female.
Character mistake: When Tom goes into cardiac arrest, the doctor uses the defibrillator paddles on him, but she uses them whilst the hospital gown is still on him. A defibrillator must be used on bare skin if the electricity is supposed to get through to his heart. (01:08:55)
Character mistake: Leland Palmer handles Laura's body without any gloves when wrapping her and disposing of the body. As with any respectable FBI investigation, upon finding her body and checking for fingerprints, they should've connected Leland to Laura's death within days. (02:05:00)
Character mistake: Ashley should be smart enough to know not to wear high heels while buffing the bowling alley lane. They might break or scuff up the floor, she should've worn sneakers or sandals.
Character mistake: At the beginning of the movie, during "Provincial Life", we see a fat lady trying on a hat in a hat store. The sign over the window, in French, reads "Chapeau" (hat). The correct way to identify that store would have been "Chapeaux" (hats) or "Chapelier" (hatter).
Character mistake: They keep calling the vehicle a milk truck but it says "ice cream" on it. (00:23:55)
Character mistake: At the psychiatric ward, Ray says that Vigo is a XVII century tyrant; it's not a very fitting way to describe him, since he saw the XVII century for just a decade; as the book mentioned, he lived from 1505 to 1610 and was the scourge of Carpathia for the XVI century. (01:16:15)
Suggested correction: Not a mistake, Vigo was a tyrant in the 16th and 17th centuries, Ray chose to label him a 17th century tyrant because that's the century he died in. It would be like calling Osama bin Laden a 21st century terrorist, which is correct, even though he also committed terrorist acts in the 20th century.
Character mistake: At the beginning of the movie, Marnie states that she is 13 years old. When Grandma Aggie comes to visit, she tells Mom that it is Marnie's 13th Halloween. Since everyone celebrates their first Halloween before they turn one, if Marnie is 13 the events of this movie would occur on her 14th Halloween, meaning her powers would have faded by now.
Character mistake: When Hook has Pan under control, the kids start to say "I believe in you" in turns. The second one, a red haired boy, can't help staring at the camera.
Character mistake: When Harry takes the kids to his business, he's showing them how he "restores" cars. After putting the bumper on, Harry says, "Transmission. The sawdust quietens the gears and let's the engine run as sweet as a nut." Putting sawdust into the transmission would not change how the engine runs as they are two separate components. It may make the transmission quieter but would have zero effect on the engine.
Character mistake: When Mike pulls out the first Scare Report, the word "yield" is spelled wrong.
Character mistake: When Charles comes down to breakfast the evening after Elvira arrived, he comments to Ruth what a wonderful day it is, "not a cloud in the sky." But that's wrong; there's a low cloud bank and the rest is murky and gloomy.