Stanley Jobson (Hugh Jackman) is an elite hacker who infected the FBI's Carnivore program with a potent computer virus, delaying its deployment by several years. For this, he was arrested by Agent Roberts (Don Cheadle), convicted of computer crimes and spent two years in Leavenworth. A condition of his parole is that he is forbidden from touching, much less using, a computer. His ex-wife, Melissa, has sole custody over their daughter Holly and some form of restraining order against Stanley from seeing Holly.
While Stanley is at home in rural Texas practicing his golf swing, a woman named Ginger Knowles (Halle Berry) shows up to solicit his hacking skills for her boss Gabriel Shear (John Travolta). For an initial $100,000 he agrees to meet with Gabriel. He and Ginger fly to Los Angeles, California and meet Gabriel in a night club. Gabriel pressures Stanley right-then-and-there to hack a government system in 60 seconds while at gun point and receiving oral sex. Although it was just a test (the gun was not loaded) Stanley succeeded in hacking the system, a feat that Gabriel had not anticipated.
At Gabriel's house he convinces Stanley to write a worm for $10 million that steals money from a secret government slush fund on the order of $9.5 billion. Gabriel reveals to Stanley that he works for an organization called the Black Cell that was started by J. Edgar Hoover in the 1950s, which is responsible for retaliatory attacks against terrorists who have attacked Americans. It is currently headed by Senator Reisman. Reisman discovers that the FBI has caught onto Gabriel and attempts to pull the plug. After Gabriel refuses to terminate plans Reisman attempts to have Gabriel killed, which fails. Gabriel tracks the Senator down while he is fly fishing in Bend, Oregon and kills Reisman.
Gabriel proceeds with his plan and raids the local branch of the WORLDBANC. He takes hostages and deploys Stanley's worm. After stealing the $9.5B he boards the hostages and his crew on a bus out of the bank. Gabriel demands a plane at the local airport (a hostage negotiation cliché) but it was a diversion. An S-64 Aircrane swoops down, lifts the bus, and releases it on the rooftop of a skyscraper. From the rooftop, Gabriel departs with his team in a helicopter which is shot down by Stanley with a rocket-propelled grenade. At the morgue, Stanley realizes it was more misdirection and Gabriel was not on the helicopter and "Gabriel Shear" is an alias.
The end of the film shows Ginger and "Gabriel" in Monte Carlo transferring that $9.5B into other accounts. The final scene shows a yacht being destroyed and a news anchor voice narrating that a suspected terrorist died on that yacht, althought the dvd does contain an alternate ending wherein Ginger is told in the bank that the account is already empty, alluding to the possibility that Stanley has played one final trick on them and taken the money himself.