Brothers Zach and Gray Mitchell visit Jurassic World, a dinosaur theme park on Isla Nublar, of which their aunt Claire Dearing is the operations manager. Claire assigns her assistant Zara as the boys’ guide, but they evade her and explore on their own. Elsewhere on the island, U.S. Navy veteran and ethologist Owen Grady has been training four Velociraptors named Blue, Echo, Delta, and Charlie, and researching their intelligence. Based on the raptors’ ability to follow commands, head of InGen security Vic Hoskins believes that the animals can be weaponized, an idea Owen and his assistant Barry strongly oppose.
Prior to its opening, Claire and park owner Simon Masrani inspect the park’s newest attraction, the Indominus rex, a transgenic dinosaur created by geneticist Dr. Henry Wu. Masrani tasks Owen with evaluating the enclosure. Owen warns Claire that the Indominus lacks social skills, making it dangerous and unpredictable. When it seems that the Indominus has escaped, Owen and two park workers enter the enclosure. The Indominus, which can camouflage itself and mask its heat signature, suddenly appears. Owen survives, but it devours the other two men before escaping into the island’s interior. Owen advises Masrani to have the Indominus executed, but to protect his company’s investment, Masrani dispatches a specialized unit to subdue it with non-lethal weaponry, so it can safely be returned to its paddock. After most of the unit is slaughtered, Claire orders the evacuation of the island’s northern sector.
While exploring the park in a tour vehicle, Zach and Gray enter a restricted area. The Indominus arrives and destroys the vehicle but the boys narrowly escape. They find the ruins of the original Jurassic Park visitor center, repair an old Jeep Wrangler, and drive back to the park resort. As Claire and Owen search for the boys, they barely escape the Indominus. Masrani and two troopers hunt down the Indominus by helicopter, but it breaks into the park’s aviary. The aviary’s pterosaurs crash Masrani’s helicopter, killing all three inside, before converging onto the resort, and terrorizing many of the visitors, including Zara who was later devoured by the park’s Mosasaurus. Gray and Zach find Owen and Claire at the resort as armed personnel shoot down the pterosaurs.
Assuming command, Hoskins orders the raptors to be used to track the Indominus. Forced to comply, Owen leads the raptors. Upon finding the Indominus, the dinosaurs begin communicating among themselves. Owen realizes that the Indominus has Velociraptor DNA in it and it usurps Owen’s dominance, becoming the pack’s new alpha. Troops fire on the Indominus, but it escapes. The raptors slaughter most of the troops, but they do manage to kill Charlie. Hoskins evacuates Wu and the dinosaur embryos from the island to protect Wu’s research. Owen, Claire, and the boys find Hoskins at the lab trying to secure more embryos, but Delta breaks in and kills him.
Owen re-establishes his bond with the three surviving raptors before the Indominus reappears. They attack the Indominus, but Delta and Echo are killed while Blue is knocked unconscious. Claire releases the veteran Tyrannosaurus rex from its paddock and lures it into a decisive battle with the Indominus, which gains the advantage over the T. rex until Blue recovers and rejoins the battle. They corner the Indominus at the lagoon’s edge, where it is dragged underwater by the park’s Mosasaurus. The survivors are evacuated and the island is abandoned again. Zach and Gray are reunited with their parents, while Owen and Claire decide to stay together.