Revealing mistake: In the disco scene, the DJ is playing music, but the Pioneer decks and the DJ Mixer are not even turned on, as no lights are showing.
Revealing mistake: During the scene at the restaurant in Montenegro (actually filmed in the Czech Republic) you see a payphone with a Czech Telecom logo on it (itself a piece of history as these are all now rebranded O2). (01:57:50)
Revealing mistake: In the first major battle between the 300 Spartans and the Persians, Leonidas is slaughtering the Persians and the speed of the scene goes from slow motion to fast motion, you see very realistic CGI blood. When the blood hits the the ground it suddenly disappears. This happens many times during this long and awesome scene.
Revealing mistake: When the Bronco is underwater at the end of the movie, Claire's hands are tied to the steering wheel. Doug rips the steering wheel off. Anyone who has worked on cars knows you need a puller to get a steering wheel off. Also, the steering wheel is gone when Claire swims to the surface.
Revealing mistake: When Alex sets-off the smoke bomb in the warehouse, the smoke is coming up from under the grate in the floor nowhere near the DS.
Revealing mistake: Watch closely when the first two 'slaves' run for their freedom amidst flying spears. When Jaguar Paw's friend (the chunky fellow) gets speared, it is a 'through the armpit' effect. When he's gasping for breath in the next shot, the entry of the spear is actually more in the middle of his chest.Kate Giles
Revealing mistake: When Bobby is being chased by the police in his Dad's car it is blatantly obvious that a stunt double is driving.
Revealing mistake: When Jack drives the bus down the alley, it knocks a series of A/C units off a building. The last one comes open and there is obviously nothing inside. (01:12:35)
Revealing mistake: When the dragon is hatching, a light bulb is visible just behind and to the left of her egg. (00:14:10)
Revealing mistake: Watch carefully after Angela is thrown through the windshield of the bus. There is a shot of diamonds and blood-stained glass scattering on the floor. But in reality, there is a shot of plain diamonds falling and the bloody glass is faded in during the middle of the shot. Most visible on the edges of the screen, where the pieces emerge from nowhere.