Autobots and Decepticons are at war, with humans on the sidelines. Optimus Prime is gone. The key to saving our future lies buried in the secrets of the past, in the hidden history of Transformers on Earth.

As humanity picks up the pieces, following the conclusion of "Transformers: Dark of the Moon," Autobots and Decepticons have all but vanished from the face of the planet. However, a group of powerful, ingenious businessman and scientists attempt to learn from past Transformer incursions and push the boundaries of technology beyond what they can control - all while an ancient, powerful Transformer menace sets Earth in his cross-hairs.

The Autobots continue to work for NEST, now no longer in secret. But after discovering a strange artifact during a mission in Chernobyl, it becomes apparent to Optimus Prime that the United States government has been less than forthright with them.

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.

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.