Revealing mistake: When Jake is sliding on the floor at the mall trying to grab his retainer, streak marks are visible on the floor from where they practised the shot.
Continuity mistake: At the prison visiting "Uncle Sally", Dickie sets a box of matches on top of his cigarettes. A little later, the matchbox is behind the cigarettes and the cigarettes are angled about 45° more away from the ashtray. (00:48:12)
Other mistake: Rebecca electrocuted the giant sand worm within 3' of the spaceship. After Lt Astrid arrives, some views show Rebecca out in the open, but the camera should have been obstructed by the spaceship because following front views still show Rebecca next to the spaceship. Also, at least part of the dead giant sand worm probably should have been visible at times but was not. (00:51:55 - 00:52:20)
Factual error: Dr. Boxer is told the experimented upon baboon died. He asks that an autopsy be performed. Autopsies are performed on humans. A post-mortem examination on animals is called a necropsy. (01:01:45)
Factual error: The Channel 5 WNP Newscaster said, "it is now believed he [District Attorney Berdido] and his family were killed..." and running along the bottom of the screen was "4 confirmed dead in Fort Lauderdale gas explosion." This was a LIVE report showing two streams of water onto the house still burning inside. An investigation would barely, if at all, be started at this time and no-one would be "confirmed dead" this early. It would not even be known if anyone was home when the house exploded. (00:04:34 - 00:04:55)
Continuity mistake: Leonardo DiCaprio's phone is shown attached to his car dashboard. He gets out of his car, all the while, looking up toward the sky. The next scene shows him grabbing his phone from his pocket while standing outside his car. (01:36:06 - 01:36:56)
Other mistake: Det. Martinez told Peter he couldn't do anything about his belief that Charles was in his penthouse (and took his dog) without the necessary evidence. However, the detective filed stalking charges against Peter based on Charles' statement that he was being stalked, which was without evidence. The charge of stalking was also far-fetched and the detective should have had enough sense to realise that Charles would not be in fear of his safety over Peter's presence or behavior.
Visible crew/equipment: When Edee is driving up to the cabin for the first time, just before they get there, there are a couple of shots looking through the windshield showing her looking out. A couple of the shots have a shadow of the top of the camera very visible. You can see the mic antenna on it.
Continuity mistake: Before Jen gets on the yacht, Aileen's green halter strap can be seen because the left side of her hair is on or over her shoulder. When Jen gets on board, Aileen's hair is in front, covering up the green strap. The camera shifts when Lewis is hugging Jen and Aileen's green strap is visible again with the left side of her hair behind her. There is no noticeable wind and Eileen is standing in the same place. (00:32:10)
Revealing mistake: After Charlie talks to Emma in Francine's old bedroom and is standing in the doorway, the background (segment of the hallway) is obviously fake. Shown are less than five of the top steps on the staircase, only a fraction of the size of real steps. The lower section of the banister is also a reduced size. (01:31:35)
Character mistake: After banker Karl was reported missing from his home, the police detective did not even think to locate his car - which he could have merely driven away in (meaning he was not kidnapped).
Revealing mistake: When Alana is walking toward the students, the hedges are mostly dark green, sheared level across the top, and reach to her elbows. Later (after Gary tells Alana he will take a mirror), the hedges turn mostly yellow and flower-like across the top, are quite uneven, and are as high as her shoulders in spots. (Use of a green screen is apparent). (00:00:40 - 00:01:26)
Suggested correction: One look at the scene make it apparent this entry is totally incorrect. The bushes look natural. The yellowness is just colour grading. There is no sign of green screen usage whatsoever. It would make no sense for this film, especially if you realise that director PT Anderson is known to be very much against the use of any sort of VFX or green screening.
Continuity mistake: The police officer stopped his cruiser some distance behind Malik's SUV, but the cruiser was closer to Malik's SUV when the officer was talking to him and when he pulled his gun on him. (00:19:27 - 00:21:55)
Revealing mistake: During one of the chase scenes, an SUV hits a rock barrier and flips over landing on its top. The car spins around, and we see that it is empty. The driver then climbs out as if he was just in the vehicle.
Continuity mistake: The door had multiple small rectangular glass panes enclosed in wood frames, but the glass pane that Alan Schaefer's head/body went through was larger and no wood frames were visible. (00:40:28)
Other mistake: At the end of the movie the soldiers handcuff Farid despite the fact that he only has one hand.
Revealing mistake: When Rachel sees the burning car, the blatant CGI flames are moving in slo-mo.
Visible crew/equipment: When the group realise they have triggered the alarm system, one of them says "Shhh listen" and the boom microphone appears briefly above his head. (00:45:26)
Revealing mistake: At first glance, the cow at the start may have looked real, but its limited mouth movement while eating grass (without any grass being pulled out) indicates it was a mechanical cow. The cow also did not move its rear end or raise its head when Fenn and Geary approached and stood right behind it. A real cow would not stay in the exact same position (motionless) that amount of time. The cow's "fur" also did not look real. (00:02:50 - 00:03:24)
Factual error: At the end of the film, Hellfire Jack returns the toy soldier to the son of the late William Hawkins in 1917. Hawkins son is shown taking it upstairs and placing it in front of a photo of his father, in between two medals. These are the British War and Victory Medals - these did not exist until 1919, and in most cases were not even issued until the 1920's.