Young teenager Sam Witwicky becomes involved in the ancient struggle between two extraterrestrial factions of transforming robots – the heroic Autobots and the evil Decepticons. Sam holds the clue to unimaginable power and the Decepticons will stop at nothing to retrieve it.

In 2035, where robots are commonplace and abide by the three laws of robotics, a technophobic cop investigates an apparent suicide. Suspecting that a robot may be responsible for the death, his investigation leads him to believe that humanity may be in danger.

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.