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)
Continuity mistake: When the news crew is interviewing Sam's parents during the credits, the way Ron holds Mojo changes. (02:15:10)
Other mistake: When Frenzy attacks Sam, the teenager wears straight leg jeans with a narrow leg opening (not boot cut) and thick-soled Nikes, seen in numerous shots, as he kicks at the Decepticon. After the cut to Mikaela (who finds the reciprocating saw), during which Frenzy has already pulled off the bottom of Sam's jeans, Sam continues to kick and scream just before he gets up and runs. Problem is Sam still wears both thick-soled Nikes, neither of which slipped off as Frenzy maniacally pulled the jeans, with narrow leg openings, from his kicking legs/feet. Impossible even in the best of circumstances.
Continuity mistake: When Sam and Mikaela handcuff all the agents, Sam is wearing a black short-sleeved tee shirt atop a blue long-sleeved tee, before putting on the hoodie. We see the dark tee sticking out when he and Mikaela climb onto Prime. Then moments later, Sam is wearing ONLY a long white short-sleeved (we see it has short sleeves when Bumblebee gives him the All Spark later, through a tear in the hoodie sleeve) tee shirt under his hoodie, when he falls from Prime, when he witnesses Bumblebee's capture and thereafter. (Earlier, after he knocks Mikaela off the moped, from that point on there is a very large hole at the back of his blue and black tees, where we see his skin under the jagged material edges, with no white material seen anywhere. We also see no sign of a long white undershirt at any time when Sam's dark tees go up, during his many action shots.)
Continuity mistake: When Banachek shows Secretary Kellar the photo of Blackout from Qatar, the photo is a photo taken of the transformer in the Beagle 2 video. It's not the photo Epps took of Blackout. You can tell because Blackout has a box-shaped body and the transformer in the photo has a slender body.
Continuity mistake: When Mikela hotwires the tow truck, it has an automatic gearshift. Later, when she is driving and Bumblebee is shooting, look closely, it's now a manual transmission.
Deliberate mistake: If you pay extremely close attention to the scene of all of the Decepticons responding to the small Transformer's message regarding the location of the Allspark, notice that the shot of the police car and the fake helicopter pilot are duplicate shots used earlier in the film.
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.
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: 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 Bumblebee is captured by Sector Seven, the camera goes back to Optimus Prime talking to Mikaela and Sam. If you look at her hair, it is loose and flowing. In the next shots when Sector Seven capture them, Mikaela's hair is tied up at the back, she had no time to tie it up.
Continuity mistake: Mikaela gets a tow truck to move Bumblebee after he lost his legs. At first, the writing on the left door says 'Mike's Towing - 800-555-0199.' When she gets out to hoist Bumblebee up, the writing on the same door has changed to 'Mike's Towing - 800-555-MIKE'.
Continuity mistake: In the beginning of the scene where the Decepticon is on Air force One they show a 747 but when they land and they show the Decepticon sneaking off the plane the Air Force One shown is a KC-135. Although you don't see the whole plane, the engines are that of a KC-135, long and slender versus big and round like a 747. Also, you can see the refueling boom, which a 747 does not have.
Continuity mistake: When we hear Sam's recording on his phone, it sounds nothing like what he actually recorded.
Continuity mistake: In the city, after Ironhide flips over the missiles that Devastator shot at him, he can be seen falling very close to the ground, but in the next shot, he is much higher up so that he can then shoot himself back up-right.
Factual error: In the scene in which the US Army SpecOps survivors of Qatar are being picked up, they were sent a Huey. However, the US Army has replaced the Hueys with the Blackhawk.
Continuity mistake: When we hear the Qatar base commander say: "4500X, something's not right," we see the sun has already set (the sky is purple) but when everyone starts to mobilize, the sun is still visible above the horizon.
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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