Visible crew/equipment: When Banachek and Simmons are talking to Sam at the entrance of the Hoover Dam, you can see the white lighting panels reflected in their sunglasses. (01:36:30)
Revealing mistake: When Sam flips over on the bike, in one shot you can see that it is a stuntman who looks much older than Sam. (00:47:55)
Visible crew/equipment: After Glen sends the message, the soldier says, "Sir, I have authenticated air strike order from Sec Def.," In the next shot, just as Prime's silver bumper beneath the grille comes into view, the reflection of the crewmember who is standing on the filming vehicle's camera platform, beside the mounted camera, is visible on the right side. (01:49:30)
Revealing mistake: In the final battle, Captain Lennox is going to shoot Blackout. He gets on a motorcycle, goes really fast, and then slides off the bike and down the street. While he is sliding, he shoots Blackout. When Lennox gets to his feet, you can see his back, and his shirt is not worn away at all. It isn't even discolored.
Continuity mistake: In the junkyard when Bumblebee is trying to get away form the "cop", after Bumblebee locks the doors with Sam and Mikaela inside, the windows continually change from being up and down.
Visible crew/equipment: During the attack on Hoover Dam, after Simmons rejects Sam's request to be brought to Bumblebee, when Simmons tells Lennox to drop his weapon, in the next overhead wideshot the grey tape marker between Lennox's and Simmons's feet is visible, as well as the tape marker at Secretary Keller's feet. (01:43:15)
Continuity mistake: When Sam and his parents are being arrested by the Sector 7 officers, inside the house Sam is wearing a blue Strokes t-shirt over a long sleeved shirt. When the shot changes and Sam and his parents are being led in hand cuffs to the police cars, a brown sweatshirt is tucked between Sam's left arm and his back due to the handcuffs. In the next shot, Sam is wearing the brown sweatshirt as he says a line of dialogue. The camera cuts to Agent Simmons of Sector 7, then goes back to Sam, who is now wearing the Strokes shirt and the brown sweatshirt is draped over his left shoulder.
Factual error: In the beginning scenes which take place in Qatar (not Bahrain), you can see tall mountains all around in the background. Qatar is surrounded by desert and a few hills such as Tuwayyir al Hamir that are up to about 325 ft in height, but it has NO tall mountains. All filming locations are in the US.
Continuity mistake: In this movie, we see a close up shot of Mikaela's hands in three separate scenes. The first is a shot from behind Mikaela and Sam where they grasp hands and the camera closes in on that. You see Mikaela's short nails, with chipped red polish. The second time we see her hands is a shot where she covers her open mouth with both of her hands in shock. Her nails are unpolished. Finally, the third time is during the ending sequence where both she and Sam have been thrown to the ground near each other. Mikaela stretches her hand toward him, they touch fingertips, and the red nail polish is back.
Continuity mistake: During the final battle, Sam rolls on the pavement and reverses direction as a jet-bot lands and transforms. The next wide shot shows Sam scurrying alongside the passenger-side fender of a black Mercedes sedan as another black car is tumbling over the Mercedes' hood, its doors wide open. This same moment repeats in the next shot, from another angle, but suddenly Sam isn't at the fender of the Mercedes- he has vanished. The angle changes again and the same moment repeats a 3rd time, and Sam is still missing. Then, a closeup shot is looking up past Sam as mayhem rages above, and the black Mercedes he huddles against is suddenly a red car. (02:01:20)
Visible crew/equipment: After the agents are handcuffed, when the Autobots transform into their respective vehicle modes as one of them says, "Roll out!", there are three black ramps positioned in front of the sidewalk, which were not there before. The Autobots use them when driving up onto the sidewalk. (01:24:20)
Continuity mistake: During Sam's family genealogy report, when he holds up Captain Witwicky's glasses to show the class, there are cracks in certain areas of both lenses. Those cracks actually change position and characteristics when we see the glasses elsewhere in the film, such as on eBay and when Prime explains their importance to Sam and Mikaela when they first meet. (00:10:15 - 00:17:40)
Other mistake: During the chase scene on the highway, when Sam says, "It's the same cop," they pan to a wide shot to show the whole freeway with the cars on it. All of the vehicles are on the wrong side of the freeway. When looking out of the back of his car, you can see the fronts of all of the cars coming towards the camera, and you can see the text on the signs facing the camera as well. You can also see crowds on the flyover, watching the filming. (01:50:05)
Continuity mistake: After class when Sam rushes to his father, who is waiting in his car, and tells him that he got an A-, the license plate is affixed to the front bumper. At the start of the next shot, the front license plate is gone, but it then reappears when they arrive at Bobby B's. (00:11:35)
Revealing mistake: When Mikaela and Sam are in his car when he gives her a ride from the lake, both windows are open but her hair doesn't blow around at all - like it would if they were really open. (00:23:00)
Factual error: The Secretary of Defense states that the remains of the defeated Decepticons were dropped into the Laurentian Abyss, "the deepest point on Earth". The deepest point on Earth is actually Challenger Deep, in the Mariana Trench. Given the location was specifically chosen BECAUSE it's the deepest point on earth, it would have been properly researched by the characters, making this a movie mistake rather than a character mistake. (02:14:50)
Visible crew/equipment: After Bumblebee locks its doors with Mikaela and Sam inside, the Camaro speeds past Barricade and does a 180° spin. Just before the shot cuts away, as the passenger door first opens there is a perfect view of the back right tire, where we can see the stunt cable attached to under the tire. (00:52:50)
Continuity mistake: In the battle scene with Frenzy in the dam, Agent Simmons uses a flamethrower to push Frenzy away a good distance from the door but in the next shot Frenzy is already halfway through the door.
Continuity mistake: When Jazz uses his magnetic hand to remove some of the guns from the Sector 7 people, the guns fly into his palm, but in the next shot, his hand is down and there are no guns in his hand or on the ground. He couldn't have put his hand down or thrown the guns away that fast between the shots. (01:22:00)
Visible crew/equipment: When the soldiers discover the telephone line in Qatar, Scorponok tears down the tower. As the tower hits the ground we get a frontal view of the soldier wearing glasses. As the soldier turns his head we can see the film crew reflected in his glasses. (00:39:05)
Answer: Because the Decepticons didn't know where Megatron ended up for the last 100 years. Bumblebee arrived on Earth as a scout to check out for any clues, found the glasses on Ebay, signalled the other Autobots, which prompted Blackout and Frenzy to investigate the base in Qatar, which lead to Blackout downloading the base computers and Frenzy hacking the computers aboard the aircraft later leading to the discovery of Megatron's whereabouts.
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