Revealing mistake: When Kikuchiyo tricks and kills the gunner, he chases him a short way, then stabs him with a sword. Even though there's a tree blocking the action, you can still see he never actually stabs him, he just lightly stabs the ground near him.
Revealing mistake: During the transport of the POWs by train (which starts about 26 mins into the film) the number on the side of the engine is visible as 719. About 3 mins (filmwise) into the journey it appears in mirror image. It appears they filmed the train moving from right to left, but throughout the film the train moves from left to right, so the film must have been reversed. It happens twice, the second time 14 min 24 sec after the first. (00:29:34)
Revealing mistake: When the German cruiser Graf Spee is seen leaving Montevideo harbour for the last time it is flying the American Stars and Stripes flag from the aft observation platform tower.
Revealing mistake: In this scene we see Cheetah jumping down from a tree to the ground. In the next shot we see Cheetah and a circle of light moves, which indicates they were using a mirror or even a light for extra lighting to brighten up the shot. This happens very briefly and is very noticeable.
Revealing mistake: When the smudge pot is set off, it's on the ground, smoke coming of the ends. A moment later, along with a huge cloud, if you look at the bottom of the scene, there's an area about five feet wide billowing smoke.
Revealing mistake: When the Remagen bridge is bombed, it is obvious that the bomber planes shown have been taken from several shots (possibly also from an earlier film) and the shots were superimposed. Also, the bombers appear transparent, and the background sky's color is unnaturally strong, too.
Revealing mistake: When Caesar's ship arrives in the Alexandria marketplace, he tells his men to "go marketing" rather than force their way through the crowd with swords. Rufio says "you're not serious?" He then silently mouths along with Caesar's reply, "We shall shop our way to the palace steps." (00:11:30)
Revealing mistake: Near the beginning, after the corporal has burned his finger and tells the other corporal that Lawrence is balmy, O'Toole begins to run up the stairs to meet with a general. After O'Toole is out of view of the camera, you can tell he has stopped running up the stairs by his shadow on the wall not moving, because he knows that the director is about to shout "cut".
Revealing mistake: As Sgt. Highway turns the dead body with a cigar in the pocket you can see its right arm move to avoid twisting. (01:38:05)
Revealing mistake: In the scene where a British soldier (Williams) and Sgt. Joe Gunn (Humphrey Bogart) are in a trench, the British soldier is shot dead by a German sniper. Joe Gunn moves in for a closer look and it can be seen that the "dead" soldier is breathing, his shoulder is moving. (01:15:30)
Revealing mistake: When the defective shell is about to fall, the ground has no sand mounts. Couple shots later, now on the floor, the shell turns around following Chaplin. Watch and you'll see that a sand mount has magically appeared close to the shell to hide the white mechanism that makes the bullet turn.
Revealing mistake: In the scene where there is a air battle between a DC-3 transport, a American Corsair fighter and a Japanese Zero fighter we see some shots where model aircraft were used - it can be seen that there are wires holding the three aircraft up.
Revealing mistake: In the scene where the boy is shot in the leg and the carried away by an unionist soldier you can see more union soldiers storm past them. The bayonets of the soldiers are obviously made of rubber as they are dangling while the rifles are moved up and down by the running soldiers.
Revealing mistake: The bayonet used by Private Williams after the death of his Sergeant Major is flexible and made of rubber.
Revealing mistake: After Clint has shot the 3 would-be rapists, he is rifling through the pockets of the dead men. As he checks the pockets of the first guy he shot the "dead" guy in the background is breathing.
Revealing mistake: In various scenes before the Compass Rose is supposed to be fitted with radar, it's obvious the 'lantern' round the already fitted radar aerial has been removed and the aerial itself covered with a tarpaulin to simulate the ship in its earlier, pre-radar, state.
Revealing mistake: During the Flak attack on the B25s Arfy notices Orr's plane going down. The scene cuts to a smoking plane going down at a steep angle, but you can see the plane was flying straight and the film turned at an angle as the colors on the horizon are also at a steep angle.
Revealing mistake: Right at the beginning of the movie, an alien blasts Lieutenant Smalls and he drops his rifle. The weapon wobbles, revealing it's a rubber prop rifle. (00:01:55)
Revealing mistake: Whenever our heroes are shown firing the Vickers guns on or off the vehicles, they are very obviously fitted with blank-fire adapters to the front. The belts of ammunition for them throughout the film are also blanks - the cases are visible, but the bullets that should project out the other side of the belt are not present.
Revealing mistake: Most of the tank battle scenes throughout the movie are low budget CGI.