Factual error: When the Secretary of Defense is talking about dispatching battle groups to various places around the planet, we get various shots of a Carrier Battle Group. Now this movie is set in 2007. On the aft end of the carrier are F-14 Tomcats. The last Tomcat was retired from service in September of 2006, almost a year before the movie takes place.
Visible crew/equipment: Upon arrival at Hoover Dam, just as Sam exits the SUV the reflection of the camera/crane is visible on the vehicle's black surface, at the left, just before it tracks backwards into an overhead shot. (01:34:25)
Visible crew/equipment: In the aerial shot, as Starscream flies past the glass building with the names "Deloitte and Touche" (before his first attack on those in Mission City), we see the reflection of the filming helicopter behind Starscream, just beneath the names. (01:53:20)
Continuity mistake: When Bumblebee is caught, so are Sam and Mikaela. They were on the ground being handcuffed. But then Sam gets away and starts running for Bumblebee to stop him from being frozen. Sam is no longer handcuffed at this point.
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: When Frenzy is attacking boxer wearing Sam at the fence, Sam's right sleeve at the elbow gets torn while fighting the little lunatic. That large hole disappears when Mikaela arrives with the DeWalt Reciprocating Saw. (00:54:20)
Continuity mistake: When Sam, who is wearing boxers, is running from away Frenzy there is a large tear on his left sleeve, at the elbow. When Sam reaches the fence Frenzy attacks him, and as Sam covers his head with his arms we see the tear is gone from his left sleeve (viewer's right). (00:54:05)
Revealing mistake: A yellow Pontiac GTO gets shot up, then gets blown in half with the rear end landing inside a shop window. If you look at the sideskirt of the car before it gets destroyed, you can see the cut already in the sideskirt where it will split apart. (02:01:20)
Visible crew/equipment: When Sam is at Bobby Bolivia's cars dealership intending to buy the Chevrolet Camaro and all the cars' windows explode, as the camera turns around a shocked Bobby Bolivia the shadow of a boom microphone is visible on his face.
Visible crew/equipment: When Sam is brought by his father to the Porsche's dealership at the beginning of the movie you can see the camera car reflected on the building's glass while chasing them.
Continuity mistake: After Sam knocks Mikaela off of her moped, he tells her to get in the car, and she climbs onto the passengers seat, while Sam get into the drivers seat. But in the next shot, there is no one visible on the passenger side of the car. It is best visible just before the lens flare. (00:51:40)
Continuity mistake: At Hoover Dam, when the soldiers salute Keller the clock reads 10:00, then as Keller, the soldiers, Maggie and Glen walk away in the background, when Simmons tells Sam that they got off to a bad start the clock reads 11:35, and next shot when Banacheck interrupts it reads 11:43. Also when Simmons talks to Mikaela and Sam the word "Nevada" is gone and it only reads "Time" under the clock. Then when Banacheck says, "Come with me, we'll talk about your car," the word "Nevada" is back under the clock. (01:35:25)
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)
Continuity mistake: At the park, when Sam decides to drive Mikaela home, Miles is in the car with his right arm (viewer's left) up behind his head, but in his close-ups his arm is down. (00:22:30)
Continuity mistake: In class for his genealogy report, when Sam begins to dump his great-great-grandfather's belongings onto the desk, while the backpack is upside-down it turns around from front to back, between the wideshot and next close-up. (00:08:55)
Continuity mistake: When Sam's parents begin knocking on his bedroom door, Prime says, "Ratchet, point the light," and nothing is on the bathroom windowsill, but when Ron is searches Sam's bathroom with the flashlight there are two small overturned flower pots lying on that windowsill. The flower pots are gone again when Ironhide asks, "The parents are very irritating, can I take them out? (01:14:05)
Continuity mistake: When Prime lifts Mikaela up to Sam's bathroom window, there are two baseballs in acrylic display cases and another object (looks like a vintage camera) on the windowsill (beside the tub). Then when Sam runs to that window and sees the Autobots parked as if it were a "truckstop", all those items disappear and are replaced by two small overturned flowers pots. (01:11:55)
Continuity mistake: When Scorponok's tail is being examined aboard the transport plane, as it curls itself to strike, Epps jumps back with his hands up near his head, but next shot Epps's hand is positioned on the table for the dramatic near miss. (01:06:50)
Continuity mistake: When Sam and Mikaela are in the SUV with Simmons, the look of the backseat of the vehicle, between the two teenagers, changes when Prime appears, and provides them with his version of a sun-roof.
Continuity mistake: After Sam takes off running with the All Spark, heading for the building, Prime is shown driving down the street towards a collection of garbage bins. In the next shot, before Prime hits them, all the garbage bins are set up very differently. (01:59:45)
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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