In 1988, an 11-year-old Dade "Zero Cool" Murphy (played by Max Ligosh) faces legal troubles when he is apprehended for crashing a remarkable 1,507 computer systems in just one day, resulting in a 7-point drop on the New York Stock Exchange. As a consequence of his actions, he is prohibited from using computers or touch-tone telephones until he reaches his 18th birthday.
As Dade, portrayed by Jonny Lee Miller, approaches adulthood, his divorced mother relocates to New York City for work. Once he turns 18, he executes a clever plan to hack a local television station by tricking a security guard into revealing the modem's phone number—employing a technique known as social engineering. To his surprise, he gets challenged by another hacker known as "Acid Burn," during which he adopts his new alias, Crash Override.
At Stanton High School, Dade crosses paths with Kate Libby (played by Angelina Jolie), who is responsible for giving him a tour. However, their initial interaction spirals into a rivalry once Dade realizes that Kate is indeed the hacker behind the "Acid Burn" handle.
The situation escalates when novice hacker Joey Pardella (Jesse Bradford) makes headlines by infiltrating Ellingson Mineral Company's supercomputer, boasting of his elite hacking skills to his group. Unfortunately, his actions trigger an alarm with Hal (Penn Jillette), the company's IT worker. Eugene "The Plague" Belford (Fisher Stevens), the computer security officer, discovers that Joey's download could expose his own embezzlement schemes. The Plague enlists the help of the U.S. Secret Service, falsely claiming that the file holds the key to a devastating computer virus capable of destroying the company's oil fleet.
Despite Joey's arrest and the Secret Service’s thorough search of his computer, they find nothing, as the incriminating files are cleverly hidden. In retaliation, Dade and Kate challenge each other to a hacking duel, further pulling in their friends: Ramon Sanchez (Renoly Santiago), known as "The Phantom Phreak," Emmanuel Goldstein (Matthew Lillard), dubbed "Cereal Killer," and Paul Cook (Laurence Mason), affectionately referred to as "Lord Nikon" for his photographic memory, who agree to mediate the rivalry.
After Joey's release, he discreetly informs Phantom Phreak about the hidden disk containing vital information. However, realizing they are being tracked by the Secret Service, Phreak is subsequently arrested. Avoiding conflict, Dade initially resists Kate's plea for assistance in securing another copy of the disk for safekeeping, due to his criminal past. Determined to aid their cause, Kate, with help from Cereal Killer, implores Dade to create a duplicate of the disk.
When The Plague attempts to coerce Dade into helping him locate the hacker responsible for the breach—first by offering him a top-notch laptop and later by threatening his mother—he reluctantly agrees to assist with the situation.
In a desperate attempt to uncover the true nature of the disk, Kate, Lord Nikon, Cereal Killer, and Dade collaborate, burning the midnight oil to expose its content. They ultimately determine that it has been structured to illegally siphon off $25 million from Ellingson transactions. With this information, Dade confronts the Plague, exposing his involvement in the malicious scheme due to his eagerness for Kate's disk copy.
Fueled by their newfound knowledge, the group of hackers devises a plan to disrupt Gibson once more. They rummage through garbage for important employee memos and passwords, while Cereal Killer sets up a hidden microphone in the offices of Ellingson, and Nikon takes the role of a delivery boy to discreetly record passwords. With the deadline drawing near, they learn that the Da Vinci virus will activate imminently, which would divert attention from the ongoing embezzlement.
To rally their plan, they seek assistance from Razor and Blade, the renowned hosts of a hacker-centric show, "Hack the Planet."
As the hackers launch their cyber offensive from Grand Central Station the following day, they face initial resistance from The Plague. However, thanks to a worldwide network of hackers and support from Razor and Blade, they are able to distract The Plague long enough for Dade to download the critical file.
Eventually, Dade and his team are apprehended, but he discreetly signals Cereal Killer, who is concealed among the crowd, that he has discarded the disk. During their interrogation, Razor and Blade transmit live footage exposing the plot, prompting the arrest of The Plague as he attempts to flee under the alias "Mr. Babbage."
With their names vindicated, Dade and Kate share a moment on a date, where Kate makes a dazzling appearance in a dress. The good times continue on a rooftop pool, as their friends joyously showcase their latest hack that lights up adjacent buildings with the message: "CRASH AND BURN."
