Continuity mistake: When Mikaela looks under the hood and fiddles with Bumblebee's distributor cap, her long hair is either behind her shoulders or in front, depending on the angle of the shot. (00:25:15)
Continuity mistake: When Mikaela looks under Bumblebee's hood, in close-up shots, her tummy is shiny and oily. In other shots, it is completely dry. (00:25:25)
Continuity mistake: At the Pentagon, when Maggie is sitting with her team of 'experts' and one suggests Iran, in the shot facing Maggie's back her file folder is closed and lying on the table in front of her, but in the next shot, she closes the open folder. Between these two shots, the analyst to her right goes from holding his headset by his ear, to holding a pen on the book in front of him. (00:27:50)
Continuity mistake: Before Frenzy goes to the POTUS mainframe, aboard Air Force One, in the overhead shot of the cabin the seated Secret Service agent holds in both hands the unopened USA Today, with the back's weather page facing out. Next shot, the newspaper is open in his hands. (00:28:10)
Continuity mistake: Aboard Air Force One, when Frenzy kills the first two Secret Service agents, the second agent falls back into the hallway, but his feet are still in the room over the bottom raised lip of the doorway. When the third agent fires on Frenzy, the legs of that second agent are lying flat on the room's floor, right beside the first agent that was hit. Note that the agent's legs are also beside the shelving unit, which is a good distance from the door. (00:31:45)
Continuity mistake: After Frenzy uses the POTUS mainframe aboard Air Force One, when he kills the third agent the man falls backward towards the back wall, but in the next shot as the other agents arrive, the body faces the opposite way. (00:32:05)
Revealing mistake: At night, when Sam's car is running away by itself, you can see out of the windows that it was filmed in broad daylight. (00:33:45)
Continuity mistake: When Sam pursues Bumblebee on his bike, as he is on the phone with 911 there is a close-up of Sam's feet pedaling. After Bumblebee breaks through the gate, there is another close-up of Sam's feet pedaling, but now the gears/chain are different. (00:33:50)
Continuity mistake: In the scene when Sam is being chased by two dogs and is led into a strange-looking place, when Sam climbs on top of a barrel, notice that the dogs disappear once Bumblebee drives in. Also notice that when Bumblebee drives into that place, he does a 180-degree slide, and in the next shot he's seen circling around Sam. (00:34:10)
Continuity mistake: In the scene where Sam is being interrogated at the police station, the cop catches the drug bottle with the bottom facing up. When it cuts, the top is facing up. (00:38:20)
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)
Factual error: While fighting Scorponok in Qatar, the special ops team requests a gunship to attack with 105 shells. The gunships confirms but no 105mm shot is fired. The gunships fires three rapidly firing cannons within 17 seconds. 105mm shells cause a massive explosion upon impact, and aren't reloaded that rapidly because of their weight. (00:44:05)
Visible crew/equipment: After the fight with Scorponok, the soldiers are waiting for the smoke cloud to settle. As the camera is moving behind the soldiers, a camera shadow is moving to the bottom left of the screen. (00:44:25)
Continuity mistake: When Maggie arrives at Glen's house, in the shot facing him as he shouts at his grandmother, Maggie's open empty right hand is up just as it cuts to the next shot, but now her compact is in her right hand. (00:45:45)
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)
Continuity mistake: When Sam grabs his mom's pink bike, there is nothing in the white basket at the handlebars as he flees from Bumblebee. However, at the start of the shot just before the tire hits the broken concrete, a square pink pillow suddenly appears in the basket, before flying out as Sam flips over. (00:48:10)
Continuity mistake: After Sam is knocked off the pink bike, he ends up on the ground as Barricade, aka the police cruiser, drives forward causing Sam to keep backing up, which leaves the bike near the back of the cruiser. Yet, when Barricade threatens Sam with its weapons, the bike is right beside the cruiser's front end again. (00:49:35)
Visible crew/equipment: When Sam is talking to Barricade, in the shot taken inside the car, a camera is reflected by the windshield. (00:49:55)
Continuity mistake: When Sam is being chased by Barricade, he is thrown on the windshield of a car and then mutters about it being a bad dream. In the next shot, a wheel and other junk has suddenly appeared on the car's roof. (00:50:35)
Continuity mistake: When Barricade interrogates Sam about the glasses, the cracks on the shattered glass windshield under Sam disappear, reappear and change characteristics between the interior (inside the car), overhead and close-up shots. (00:50:35)
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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