Audio problem: When Lennox is speaking to his wife via the PC, when we hear him say, "Oh my goodness, look at her. She's getting so big," there is no mouth movement whatsoever. (00:05:05)
Audio problem: Before they leave for Mission City, Lennox tells Keller, "Sir, you gotta figure out some way to get word out..." Then in the next shot, as Lennox shouts, "Let's move!" his mouth stays open - not forming the "m" with his lips to produce the word "move", which we hear very clearly (it looks as if he really said, "Let's go!"). Changes in dialogue are done during ADR and often are not in sync with mouth movements seen onscreen. (01:45:45)
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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