The Autobots learn of a Cybertronian spacecraft hidden on the moon, and race against the Decepticons to reach it and to learn its secrets.
Sam Witwicky leaves the Autobots behind for a normal life. But when his mind is filled with cryptic symbols, the Decepticons target him and he is dragged back into the Transformers' war.
Former cop Brian O'Conner is called upon to bust a dangerous criminal and he recruits the help of a former childhood friend and street racer who has a chance to redeem himself.
An ancient struggle between two Cybertronian races, the heroic Autobots and the evil Decepticons, comes to Earth, with a clue to the ultimate power held by a teenager.