Goofs

When Quentin drops Holloway, the "clothes rope" is still hanging from the door, under Quentin, and held by the others in the room. But after the cutaway, the rope has disappeared.

Leaven cracks a lens on her glasses in the beginning of the film. However, during some shots, the crack in the lens is missing.

Quentin beats Worth brutally with a boot, clearly ready to kill him or at least to knock him out. However, Worth stands up again with only one bruise under his right eye, a single scratch, and a stream of blood running from his ear. These are what Star Trek fans call "tasteful wounds," referring to Captain Kirk frequently receiving a thin slice of blood across the cheekbone, chest, or shoulder.

As the film opens, the image of an eye is panned in close-up. It appears to be blue. After the close-up changes to an overhead shot of the man, Alderson, lying on the floor, we see that his eyes are certainly brown. This is also noted in the shot of him being seen from the other room as he looks into the room, past the camera. You see his face straight-on, and his eyes are brown.

Throughout the movie they are told to suck on the buttons from their shirts. In one scene, once Holloway climbs into the next room, Quentin is sucking on his button. He immediately speaks to Worth, muddling some words because of the button in his mouth. All of a sudden, the button disappears from his mouth and is in his hand again, and he then puts it back into his mouth.

Screams can easily be heard through closed doors, but the sound-activated room does not "hear" anything through a closed door when the conversation gets quite "animated" before they enter that room. Also, the sound of a car which the human ear can hear from the inside of the sound-activated room does not trigger it either. However, the sound activation depends on sound waves hitting the inside of the walls rather than the outside.

Leaven uses a common, plastic clothing button to scratch her notes into the metal plates on various rooms within the cube. Not only is any plastic incapable of scratching any metal, the fine lines which appear in her writing could not have come from the blunt edges of her button even if it were sharp enough to score the metal.

When they get Rennes back into the room after he has been shot in the face with acid, the smoke comes from behind his head and not his face, like it should.

When Kazan lowers himself into the blue sound-activated trap room, the set cube wobbles from left to right enough to spoil the illusion (though only for about two seconds) that the cube is solid, inflexible metal.

(at 19:56) When Leaven is examining/comparing a second set of numbers, she grabs the inner door frame with her right hand to move herself closer to look. The section of the door's frame and the door itself break away from the Cube's wall/entryway ever so slightly and moves back due to the actress pulling on it.

When Quentin takes Leaven to another room because he wants to leave the others behind, you can hear the door behind him opening, but the handle isn't spinning.

The support Quentin is standing on is visible just before Kazan drops in.

When Leaven figured out that adding up the digits in the numbers gave her their coordinates in the cube, she would have almost immediately noticed that the coordinates were not in sequence from one room to the next (since the rooms were shifting).

After you enter a new room, the chamber doors automatically spin their handles and close shut. There is a scene near the end where Quentin closes a chamber door himself while another character is talking. The director admits in the commentary that this is because that particular shot was done earlier in the filming before he decided they would close automatically.

It is not clear how long the 'cube' has been operating or how many people have been inside or killed. But even if the group were the first to go through it would still mean that, if anyone were killed, the dead bodies would have to be removed, blood cleaned from walls, and so on (if only to prevent others in future from immediately seeing which rooms were traps).

This would result in the crazy situation where cleaning crews would have to be employed, travelling around the 'maze' (with each trap room being disabled just for them), potentially getting lost, accidentally meeting up with other groups or talking about the cube outside of work. A logistical nightmare.

In the last scene when Quentin stabs the young woman from behind, how did he get in that room without others noticing? He must have open a door and jump inside so no way they wouldn't notice.

After Worth tells her how big the Cube is, Leaven is somehow able to figure out where the edge is, even though at this point the group is still wrongly assuming that the cubes always remain in the same position. Basing her calculations on that wrong assumption, she couldn't have been able to figure out their position within the cube.

When Leaven first checks the rooms' set of numbers for primes, she has to think for a few seconds for each set. The first set of numbers she checks ends in 5; the second set ends in 2. Numbers ending in 2 or 5 (other than 2 and 5 themselves) by definition cannot be prime. Someone proficient at math, as Leaven is, wouldn't need to think about the numbers; she'd register they were multiples of 2 and 5 and move straight to the last number.

Kazan is supposed to be a math genius, something that the plot hinges on, but he makes several mistakes when calculating the number of prime factors to find out whether a room is trapped or not. He says that 462 has three prime factors, when it has four, that 206 has four when it only has two and that 563 has two and 911 has three when both are actually prime numbers.

Leaven claims that the problem of finding factors or primes is astronomical. This is ridiculous. It is very easy to determine if a 3-digit number is prime. The largest factor you have to check is 31, and 2, 3, 5, 7 and 11 are all very easy to check, leaving only 6 factors to check. In addition, powers of primes for 3-digit numbers are MUCH easier to check: there are only 11 primes that have squares, only 4 that have cubes, and higher than this there are only powers of 2 and 3, and those are trivial. In short, the calculations should be simple. Not astronomical.

At the end of the film Quentin grabs Kazan and is himself grabbed by Worth, which leaves him on the threshold of the room and leads to his death. This is presented as inevitable, but all Quentin needed to do to survive was to let go of Kazan and fall back into the room.