To immerse the actors, the production used full blanks for the gunfire, as opposed to half or quarter blanks, resulting in a discharge as loud as real gunfire.

In an interview with The New York Times, director Alex Garland revealed that the "Christmas Wonderland" decorations in the sniper scene were not designed for the movie. Someone had built it as an attraction and decided to leave it up after the attraction was a financial failure. Alex decided to incorporate it into the movie to symbolize the chaos in the country. "If you haven't put away the Christmas decorations, clearly something isn't right."

Jesse Plemons joined the cast just days before his scene was supposed to be shot due to the original actor dropping out. Kirsten Dunst, Jesse's wife, recommended Plemons to director Alex Garland.

Alex Garland told a reporter at the premiere that the pairing of California and Texas was, in part, to obfuscate the politics but more importantly that these two states put aside political differences to challenge an unconstitutional, fascistic, and corrupt president who is killing American civilians. He said, "Are you saying extremist politics would always remain more important than a president of this sort? That sounds crazy to me."

Alex Garland, whose family has ties to modern journalism, seems to point out the rivalries between "print" media (either paper or digital) and "television" media. The print journalists seem less supported and have a better eye for reporting escalating events, while the television media has better financial backing but is more enthralled by visual spectacle rather than instinct. Hence the TV crew is embedded with the Western Forces and has top notch equipment, while the print media is largely portrayed as rag tag.

Continuity

The front license plate falls off when they are run off the road by the military vehicle. Later scenes show the license plate back on.

Windshield is shot during the standoff at winter wonderland. Remainder of the movie it is intact.

When Sammy drives their vehicle at Jesse Plemons' character the other soldier and Jessie are several metres off to the right of Plemons but when it cuts to the impact they are all grouped close enough together that both soldiers are hit by the car and Jessie then by one of the men.

During the attack on the White House, while Jesse is taking photos of the attacking WF forces a Secret Service agent is shot in one of the rooms. As Jesse takes the photo the magazine on the agent's MP-5 appears, disappears and reappears.



Factual errors

Jessie Cullen is using a 35 mm black and white film camera. A roll of film holds 36 images, but in some battle scenes she is clicking her shutter more than 36 times without changing the roll of film.

During the assault on the president's office, in the room just outside, the floor is littered with 7.62mm brass. The only weapons being fired were 5.56mm.



Incorrectly regarded as goofs

Although set sometime in the future, Jesse (Cailee Spaeny) takes photos with a manual wind film SLR camera. Seemingly having an inexhaustible supply of film canisters, which traditionally only have either 24 or sometimes 36 frames on the roll, she snaps away with abandon, never once stopping to reload or run out of film. Not all of her moments are show, Not every instance of a photographer reloading their camera needs to be shown, particularly over the course of several days. Furthermore, she has two cameras with her (like Lee), so she has at least 48 photos she can shoot, if not 72.



Revealing mistakes

When Lee is lying on the floor in the White House, some of the shell casings next to her are 7.62mm blank casings. Identified by an elongated brass case in place of where the projectile would be.

An early aerial establishing shot of New York shows empty streets with a single military vehicle in the road. Further up the same road there is clearly visible traffic stopped where the production had blocked the street for the shot.

Jessie is shown using a manual film camera, whereas Lee uses a digital camera. There are absolutely no advantages to using film over digital in this situation, e.g. the limited number of shots per roll of film, the need to constantly reload in a fast moving, dangerous environment (possibly missing shots), having to carry around rolls of film (and to obtain them in the first place), the need to find and use chemicals for developing and printing (which Jessie appears to carry around with her, another disadvantage), the inability to instantly review a shot, not being able to change film speed between each shot, the risk of damage to the film or negative before, during and after processing, to name but a few.

Early in their trip, they drive across the median of the highway, leaving deep tracks across the grass. Although it is clearly the only way to get through, there are no previous tracks or ruts at all.



Miscellaneous

A military helicopter will not turn on its navigation lights during combat.

When Kirsten Dunst's character is shot, she is shown in black & white as if photographed by Cailee Spaeny's character. The images show her falling to the floor in a sequence which in fact could only have been captured by a camera with a motor-drive. Cailee Spaeny's camera was a manual wind on Nikon without the accessory motor-drive attachment. It would be impossible to photograph a sequence like that whilst manually winding on the film.

The Apache helicopter is equipped with a 30mm chain gun, yet the tracers and sound is indicative of a Gatling-style minigun.

While being pinned down under sniper fire, you hear the sound of the snipers gun before the bullets arrive to camera / characters.

After being run off the road, reversing, and driving away, the engine sound is of a 4 cylinder manual gearbox, while the vehicle has an auto V8 or V10 engine.



Audio/visual unsynchronized

The sprinklers in the safe town have the tock-tock-tock sound of impact sprinklers, even though they are continuous flow sprinklers.



Character error

Lee (Kirstin Dunst) says that she has to climb "ten flights of stairs" to reach the tenth floor of her hotel. In reality, starting on the first floor, she would only need to climb nine flights to reach the tenth floor.