Twelve-year-old Eric Kirby (Trevor Morgan) is parasailing near Isla Sorna, off the coast of Costa Rica with his mother’s friend, Ben Hildebrand (Marc Harelik). The boat is attacked and the crew vanishes. Ben detaches the line before the boat crashes and Eric drifts toward the island and vanishes into the forest. Paleontologist Doctor Alan Grant (Sam Neill) tries to obtain funding for his research while avoiding questions about recent events on Isla Nubar. He speaks to his friend Ellie Sattler (Laura Dern), particularly concerning the intelligence of Velociraptors. His assistant, Billy Brennan (Alessandro Nivola), uses a 3D printer to replicate a Velociraptor larynx.
Paul and Amanda Kirby (William H. Macy and Téa Leoni) offer to fund Grant’s research if he will give them an illegal aerial tour of Isla Sorna. He reluctantly agrees and flies there with Billy, the Kirbys, and their associates Udesky (Michael Jeter) and Cooper (John Diehl), and their pilot Nash (Bruce A. Young). Grant learns that they intend to land on the island. When he protests, Cooper knocks him out.
When Grant awakes, the plane is on the ground and everyone runs when a predator approaches, but Cooper is left behind. As the plane lifts off, a Spinosaurus eats Cooper. The plane hits the huge dinosaur and crashes. The Spinosaurus attacks the plane and eats Nash, swallowing the satellite phone. They flee the plane and run into a Tyrannosaurus, which is killed by the Spinosaurus as the humans make their escape.
The Kirbys admit to Grant that they are not wealthy, but a divorced middle-class family searching for their son Eric and Amanda’s boyfriend Ben. Since the government refused to help, they tricked Grant, mistakenly assuming he had knowledge of Isla Sorna. Searching for Eric and Ben, they find Ben’s corpse hanging from a parasail in a tree. Billy takes the parasail and when they find a Velociraptor nest, he takes two eggs, assuming they will be valuable.
At an InGen compound, a Velociraptor attacks them, calling for its pack. They escape by hiding in a herd of Corythosaurus and Parasaurolophus and causing a stampede. Grant and Udesky are separated from the others. The Raptors trap Udesky and try to lure Paul, Amanda, and Billy out of a tree. When that doesn’t work, they kill Udesky. Grant believes the Raptors are communicating with each other and are looking for something. He tries to slip by, but they ambush him. Young Eric attacks with tear gas and takes him to his hideout in an overturned supply truck. The next morning, all are reunited and narrowly escape the Spinosaurus.
Grant finds the Velociraptor eggs in Billy’s bag and decides to keep them to return to the Raptors, hoping they will then leave the humans alone. The party find themselves in a huge aviary-like structure containing Pteranodons. They are attacked and one flies off with Eric. Billy rescues him with a parasail but appears to be killed. They escape from the aviary but leave a cage unlocked, board a small barge, and head down the river toward the coast.
That night, they retrieve the ringing phone from a pile of Spinosaurus poo. Grant manages to phone Ellie and tell her where they are, but the Spinosaurus attacks the barge. Grant ignites leaking fuel with a flare gun and the Spinosaurus flees. The next day, they are at the coast but are surrounded by the Raptor pack. Grant blows into the Raptor larynx, confusing them, and offers the eggs. Hearing the sound of helicopters approaching, the Raptors take the eggs and vanish into the jungle. The Navy lands on the beach, summoned by Ellie. They have Billy, who is injured. As they take off, Pteranodons fly off toward the mainland.
This third film of the Jurassic Park Trilogy was not directed by Steven Spielberg, but by Joe Johnston. It was not based on a novel by Michael Crichton, though much of his work is in the film. After several tries, a script by David Koepp, with additions by John August, was approved. There were both computer-generated and animatronic dinosaurs created by Industrial Light and Magic and Stan Winston. Despite mixed reviews from critics, it was a box-office success, though not the most successful in the series. Spielberg produced. Much of the movie was filmed in Oahu and Molokai, but two months was spent building a jungle at Universal Stage 12. The Pentagon was happy to provide two Sikorsky Seahawks, four Amphibious assault vehicles, and eighty Marines. It was the shortest film of the series at 92 minutes, and reviewers complained that the end seemed rushed.
The real Spinosaurus is considered the largest predator in history—25 feet tall, 59 feet long, and weighing 12 metric tons. The heat-regulating sail is seven feet high. The first skeleton discovered appeared just before the movie production began. The animatronic T-Rex weighed nine tons, but the Spinosaurus thirteen tons. It actually bit the T-Rex’s head off. It has only three minutes of screentime. One of the Pteranodons had a wingspan of 40 feet. 250 gallons of oatmeal was used to make the pile of Spinosaurus poo. The ringing of the phone in the Spino’s gut is an homage to the crocodile in Peter Pan, who swallowed a clock when he bit Captain Hook’s hand off. The river used in the film was the same one used in The Creature from the Black Lagoon. This was the last appearance of Alan Grant until Jurassic World: Dominion in 2022.