The film is set in a world where Transformers are deemed a threat, and a government task force called Cemetery Wind is hunting them down. Optimus Prime, the leader of the Autobots, is in hiding.
The story follows Cade Yeager (played by Mark Wahlberg), a struggling inventor, who discovers an old truck in an abandoned theater. To his surprise, the truck transforms into Optimus Prime. This discovery puts Cade, his daughter Tessa (played by Nicola Peltz), and her boyfriend Shane (played by Jack Reynor) on the run from both the government and Decepticons.
The main antagonist is Harold Attinger (played by Kelsey Grammer), the head of Cemetery Wind, who makes a deal with a Transformer bounty hunter named Lockdown. Lockdown is after Optimus Prime, as the Transformers’ creators want to capture him.
As the story unfolds, it’s revealed that a Transformer bounty hunter, Lockdown, is working with the creators of the Transformers, a mysterious group referred to as the “Creators” or “Quintessons.” They have a plan to use the Transformers for their own purposes and bring about a new era of evolution.
The climax involves a massive battle in Hong Kong, where Autobots, Decepticons, and humans fight against the powerful Transformer bounty hunter Lockdown. Optimus Prime, after being heavily damaged, receives a power boost from the creators (via a powerful artifact known as the Seed) and defeats Lockdown.
The film ends with Optimus Prime flying into space, determined to confront the creators and ensure the survival of the Autobots. Meanwhile, on Earth, the remaining Autobots are granted sanctuary by the government, and Cade decides to join the fight alongside them.
“Transformers: Age of Extinction” sets the stage for future installments in the Transformers film series, introducing new elements and expanding the mythology of the Transformers universe.