What is the name of the park's chief engineer in the 1993 film?

Ray Arnold is Jurassic Park’s chief engineer in the 1993 film. He runs the park’s central control room and is responsible for its electrical, computer, and operational systems.

Arnold is played by Samuel L. Jackson and is frequently associated with the line “Hold onto your butts” before the park’s power is shut down. When Dennis Nedry sabotages the system, Arnold eventually cuts the park’s power and attempts a system reset. The restart does not restore safety: it leaves the park dependent on auxiliary power and disables the electric fences, allowing dinosaurs to escape.

A common source of confusion is the character’s first name. In the novel and some reference material, he is called John Arnold, while the film and franchise usage commonly identify him as Ray Arnold. These are not two separate engineers; they are alternate names for the same character. Dennis Nedry is the computer programmer who causes the shutdown, while Robert Muldoon is the game warden and security specialist.