Professor Levine is an expert in the field of paleontological research. He has been hearing reports of “aberrant forms” showing up around Costa Rica. He goes to Isla Sorna to investigate. The “aberrant form” seems to be a huge lizard, but it does not quite match any known lizard. On that island is the mysterious "Site B" from Jurassic Park, the dream of the late John Hammond. Site B was where they developed the dinosaurs. Levine goes to the island with his guide, Diego. Not far into the island, they encounter a small lizard that walks on it’s hind legs. Levine identified it as a species of dinosaur called compys. suddenly they all run away. A t-rex then comes out of nowhere and eats the guide. Levine manages to escape. Meanwhile, back on the mainland, a doctor (Thorne) and two of his students (Kelly and Arby) are waiting for him to show up at a meeting they had arranged. They eventually get worried and go to the island too. Doctor Thorne, Kelly, and Arby went to do research and look for Levine. They were joined by Ian Malcom, an expert in the chaos theory, and Eddie, one of Thorne's employees. They find him riding a bike along a trail. They do some research on dinosaurs living on the island for a while. Sarah Harding, a field biologist who was going to research some animals on the island, but couldn't make it right away, took a ride to the island on a boat with Lewis Dodgson and some of his crew. Dodgson is a manager at Biosyn, a company known for doing illegal things to make money. He pushes her overboard on the way. She swims the rest of the way. Dodgson and his crew try to collect dinosaur eggs. It was going well until they were attacked by a t-rex. Dodgson survived. Sarah found the others. That night, a tyrannosaur pushes part of their trailer off a cliff, nearly killing them. They hide up in a metal structure to hide from velociraptors. They had to beat them off with sticks. Unfortunately, Eddie fell off and was eaten alive, Arby managed to lock himself in a cage, And a velociraptor got his jaws stuck in the key ring with the keys to the cage and proceeded to run away. Sarah and Kelly go after it with a gun and a motorcycle and shoot it. They go and let Arby out. Then they go to make sure the chopper that was supposed to pick them up knew they were there, but it left without them. They run into a shelter. They go through to a door that leads to a dock and find a boat. They get off the island. Dodgson however, was taken by a t-rex and fed to its babies.