|“||Ah ah ah! You didn't say the magic word!||„|
|~ Dennis Nedry|
|“||Don't get cheap on me Dodgson. That was Hammond's mistake.||„|
|~ Nedry making Dodgson pay the bill for Nedry's lunch as well as deriding Hammond.|
|“||Ah, no wonder you're extinct. I'm gonna run you over when I come back down.||„|
|~ Nerdy offending the Dilophosaurus, also his ironic last words.|
Dennis Nedry is the secondary antagonist of Jurassic Park, who appears to be a troublesome and overweight computer-network engineer for the successful dinosaur-cloning faculty he was ordered to program without many details on what the park actually did and was called to the island to fix numerous bugs in the system.
Due to the low salary that left him struggling to make a living, Nedry turned on park owner John Hammond and stole dinosaur embryos to a rival theme park that has failed to make their own dinosaurs.
His meddling resulted in the dinosaurs escaping and running amok, as well as the deaths of several characters in the film.
John Hammond refused to pay him any extra money for his work. Eventually, Lewis Dodgson of Biosyn (a rival company) offered Nedry $1,500,000 to steal embryos worth of 15 dinosaur species from Jurassic Park's labs. In order to do this—and make a swift escape from the visitor center and drive away in a jeep—Nedry had to shut down the park's security systems, including the electric fences surrounding the dinosaur paddocks, with the exception of the raptor fences. Without power, the electric fences shut down, thus allowing the dinosaurs to escape.
Later that night, Dennis was driving toward the docks when he got lost during the bad storm and accidentally hit a stack of logs. His car got stuck, so he had to get out and use a winch to help him get out of this dilemma. Unfortunately, while looking for a tree to tie the other end of the winch to, he came across a juvenile Dilophosaurus. Dennis, not knowing of their aggressive nature since he knew nothing about dinosaurs, tried to shoo it away with a stick. This was a failed attempt, and the Dilophosaurus began spraying venom in Dennis's chest and then into his eyes. Dennis, now blind, attempted to make his way for his car. He wiped the venom off of his eyes and got in the car. Upon closing the door he looked to his left and saw that the Dilophosaurus had found its way into the car, where it began to eat Dennis alive.
- In the film adaptation, he is portrayed by Wayne Knight, who also portrayed Al McWhiggin, Krudsky and Emperor Zurg.
- He is made to look like the movie's main antagonist, but is never seen again after halfway into the movie, making him technically a posthumous main antagonist for the rest of the film, having indirectly released the Big One who would hunt/kill humans out of believing them as threat for her pack and Rexy who roamed around the area outside her paddock that she was not familiar with.