Character mistake: Selena Gomez drives into town in a fully restored 1967 Pontiac Le Mans, which is a long box shaped car. However, when confronted with Bill Murray and Adam Driver, Adam Driver complements her on her 1968 Pontiac Le Mans, which is a completely redesigned shorter curved body style. The two look nothing alike.
Character mistake: During the debrief meeting with the generals, Roy states the Lima Project was "some 29 years ago" and "the ship disappeared approximately 16 years into the mission." A few minutes later, Roy narrates "I was 16 when he left, 29 when he disappeared." This of course is only 13 years into the mission. (00:11:27 - 00:15:03)
Character mistake: In the Western scenes, when the characters are wearing spurs, they have the spur straps buckled on the wrong side (inside) of the foot. Spur strap buckles are supposed to be on the outside, not the inside, of the foot. Since it's wrong in every scene, it might be a comment on the TV show itself having low attention to detail.
Character mistake: In her first walk through the city with Dr. Ido, after feeding the dog her sandwich, Alita takes a flyer and reads it. Between the lines that read "Wanted" and "Murder" there is a line in Spanish that says "Querido para el asesinato." It should say "Querido por el asesinato".
Character mistake: Upon arriving to the house they say Zoe's mother committed suicide when she was 10 but later on before going back to the house to expose her step mom Sam says her mom committed suicide when she was 8. (00:16:56 - 01:17:46)
Character mistake: It's merely training, but her opponents are hostile and want to exclude her from playing, so it's funny then that they don't call Kim out for her actions being egregious fouls; she brings the ball trapping it between her feet in multiple cartwheels (you can't just hold the ball between your feet for prolonged amount of times and 'carry' it). You could also say she kicks the ball at an opponent's face on purpose, which is equally unsporting. (00:24:00)
Character mistake: Right at the beginning of the movie, introductory technobabble. "In this canister, there's a solution of protons. The canister is attached to a rotor circuit that generates the protons to the speed of light." I believe the science genius and creator of time travel mixed up the words "generate" and "accelerate" here. (00:00:50)
Character mistake: Lucas says he loves "Ascension, rules, and anti-drug campaigns", so would not be likely to encourage Max to go to Soren's party after his father grounded him... or ask what his father would do about it (double-ground him?). Even though Lucas tells Max that he has "grown a lot" in the two hours after getting home and talking to his parents about all that happened that day (which they didn't believe), we aren't told in what way(s) he has grown - but it would not be favoring violation of rules. Also, Lucas later tells Hannah and Lily at Soren's house that he loves "Ascension, rules, anti-drug campaigns, and grilled cheese." This indicates that his view on rules has not changed, reinforcing the assertion that it was out of character for Lucas to encourage Max to go Soren's party while grounded.
Character mistake: Queen is an attorney and should know how to conduct herself as a passenger in a car pulled over by police, yet she fails to behave in an acceptable way. Even though certain things may be permissible under certain circumstances, a lawyer should know exceptions and extenuating circumstances, but she apparently does not. She did not have the right to interfere with a police officer and "demand to know" or get out her cell phone to record if she was told to keep her hands where he could see them. (00:10:25)
Character mistake: Quinn told Dr. Sullivan there was "enough [morphine in the syringe] to kill you three times." If this was true (as opposed to Quinn just saying that as a scare tactic), her failure to take three vials of the antidote Narcan was a fatal error - and she only took one dose. Moreover, even if one dose was enough to counteract the morphine and get her to breathe normally, there was always a possibility that another dose or so can be needed. It is worth mentioning that it is quite a handy "coincidence" that vials of Narcan were readily available in the closed wing of the hospital. (01:12:28)
Character mistake: There are some musicians at different times in the movie. One of them is playing a moraharpa (traditional Swedish instrument, a predecessor of the nyckelharpa), but holding and playing it incorrectly. (00:38:37 - 01:39:45)
Character mistake: During her initial monologue, Katherine Newbury does the obligatory joke a 'foreign' host would make, rethorically asking where the good 'murican hosts are instead. Doing so, she mentions Martin Short, Jerry Seinfeld, Alec Baldwin. However, Martin Short is a bad example in the context of the joke, being Canadian-born.