Revealing mistake: When the earthquake strikes, there's a shot of a tall black glass building shaking. Check the lampposts and buildings around and you'll notice that it's a very obvious film negative being distorted by just wobbling it back and forth.
Continuity mistake: When afro gal Rosa is arguing with Miles and her brother at the motorcycle rally, she tells Miles he's crazy and walks off camera. But in the following shot she is suddenly 150 ft. Distance away. (00:42:13)
Character mistake: Near the beginning, Denise tells Stuart she has two small scenes in a movie, but then moments later tells him it is one whole scene.
Continuity mistake: When the man eating chicken falls off the balcony, curtains appear on the windows behind.
Revealing mistake: When the earthquake starts there are several shots of bell towers shaking. The first is the only one that moves, the rest are photos where neither the bells nor the trees around move, an obvious camera trick.
Continuity mistake: When the man at the dam presses the elevator button its red light glows. Then the shot changes and it's unlit. Shot cuts back to the previous angle and it's glowing again. (00:08:04)
Revealing mistake: When the earthquake starts there are several shots of churches shaking. None of the trees next to them are shaking, revealing the camera effect. (00:52:16)
Visible crew/equipment: Stage lights and a boom mic or filming crane are reflected on Miles' helmet when he is about to ride on the track.
Revealing mistake: After Miles' track falls down, there's a shot of a wobbling black office building. It is a mere photograph being very obviously moved back and forth. (00:52:56)
Continuity mistake: When Stewart is about to save Sam, in the wide angle Sam is lying down, both legs opened wide. In the close-up he is crouching next to the railing. This swaps back and forth.
Continuity mistake: When Sam is saving the last man in the building, he is sitting down with both hands holding the hose. From an aerial angle, half a second later, his position is completely different. (01:16:01)
Continuity mistake: When Stewart and Remy stare at the destroyed building, the sky behind is cloudy and dark, but when the shot focuses on them it is a bright and sunny day.
Visible crew/equipment: A white stage light is reflected on the kettle when Stewart visits Denise at her place. (00:14:29)
Continuity mistake: When Corry rides his bike towards the bridge it's too big for him, the seat being lower than the handlebars. A shot later the kid is way taller and the bike is tiny in comparison.
Continuity mistake: When Denise escapes from the rolling home, she trips and her jeans get covered in dust. A shot later they're clean.
Revealing mistake: When Corry's bridge wobbles, the trees and objects in the background don't, revealing that someone was shaking the bridge. (00:54:10)
Revealing mistake: When the parking lot collapses, there's a brick pillar that not only does it not break into pieces, but it bounces around, revealing it's a hollow light-weight prop. (01:38:26)
Revealing mistake: When the parking lot building collapses, check the right side where the cars are. All along the ground level there's a rectangular strip where the film of the miniature building was pasted on top of the film with the real-sized parked cars. Note how all the debris falls behind that strip, it never falls on top of the cars, as if there was a weird black hole of some sort. (01:37:54)
Continuity mistake: Sam stretches out his right arm to save the man hanging by a girder. A shot later his left arm is stretched. Then a shot later his right arm is extended.
Revealing mistake: When the California Seismological Institute collapses, the old boss is replaced by a much younger stunt. Also, his sleeves swap between rolled up or not and his tie disappears.
Chosen answer: Before he put the uniform on, he was a complete nobody, having the respect of no-one. Now that he's in uniform, he demands that people should respect him, and coupled with the powers of Martial Law (where looters can be shot on sight), takes the lack of respect too far and shoots them.
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