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)
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)
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)
Continuity mistake: After Sam knocks Mikaela off her moped, they are both on the ground right beside the moped when Bumblebee shows up, but in the overhead shot as Sam helps Mikaela up the moped is gone, not moved, just gone. (00:51:15)
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: When boxer wearing Sam begins to run away from Frenzy, in the shot facing his legs from behind he is wearing blue socks with black stripes, but then it changes to blue socks with white stripes. (00:54:00)
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)
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: Just as Mikaela comes to the rescue with the reciprocating saw, when she holds the saw up in front of her face just before she starts to hack away at Frenzy, the saw's blade clamp assembly is about 8-9 inches. After Sam kicks Frenzy, the saw on Mikaela's shoulder has a different configuration with a shorter blade clamp assembly unit. The blade differs as well. (00:54:25)
Continuity mistake: When Sam kicks Frenzy like a football in the wideshot, the right side of his boxers are torn straight up the leg, but are intact thereafter. (00:54:40)
Continuity mistake: After Mikaela hacks away at Frenzy, when Sam kicks him like a football he uses his right foot in the close-up, but his left foot in the wideshot. (00:54:40)
Continuity mistake: After Sam and Mikaela arrive at the Griffith Park Observatory (the planetarium closed for renovation), when they start to hold hands the distance between the two of them changes from farther apart, to close together, to farther apart. (00:59:35)
Continuity mistake: After Ratchet says: "The boy's pheromone levels suggest he wants to mate with the female", Mikaela scratches her head, but in the shot directly afterwards, her hand is instantly down. There is nowhere near enough time for her to put her hand down again. (01:03:50)
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 the Autobots arrive at Sam's house, we only see Optimus, Jazz, and Bumblebee driving up to the house. But when they transform, Ironhide and Ratchet have appeared and Jazz is nowhere to be seen. Later, Jazz appears from nowhere. Also, when Sector 7 arrives, the Autobots are gone without a trace. (01:09:20 - 01:15:50)
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 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 Ron (holding a flashlight and lantern) is looking through Sam's bathroom window, saying, "Judy, better call the city. We got a blown transformer...," there is no windowbox under that window, which was there earlier. Yet when Prime says "Ironhide, you know we don't harm humans! What is with you?" the rather large windowbox full of flowers is back up under that bathroom window. (01:15:50)
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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