Die Hard 4

At the start of the film, a terrorist breaches an FBI facility's computer system, and computer hackers are assassinated by the terrorist mastermind Thomas Gabriel (Timothy Olyphant), instead of being paid for their collaboration. The FBI, unaware of the killings, dispatches NYPD Police Detective John McClane (Bruce Willis) to visit a known hacker, Matthew Farrell (Justin Long), as part of their investigation regarding the breach. Gabriel's henchmen attempt to assassinate McClane and Farrell, but their targets escape. McClane transports Farrell to the FBI's Washington DC headquarters and its head, Assistant Director Bowman (Cliff Curtis), in the midst of a shutdown of the traffic system in DC. The stock market is manipulated shortly afterward, causing it to crash.

McClane is ordered to take Farrell into protective custody, and Gabriel sends more henchmen to kill the pair. McClane and Farrell evade their assassins again, and as the country's infrastructure is threatened with a major break down, Farrell tells McClane the terrorists are initiating a fire sale and that major utilities would be next. The detective and the hacker travel to a power hub in West Virginia to defend it, finding that the terrorists are already there. McClane battles terrorists while Farrell undoes the damage done to the computer system. They are contacted by Gabriel, who finds out that McClane has killed his lover Mai Lihn (Maggie Q) and angrily re-routes gas lines to destroy the hub in a gas explosion. McClane and Farrell escape once more, and on Farrell's advice, the pair visit his hacker friend the Warlock (Kevin Smith) for help. At the Warlock's home, they find out about Gabriel's background and attempt to hack into the terrorist's systems. Gabriel contacts the detective at the Warlock's home via webcam, and he shows that he has McClane's daughter Lucy (Mary Elizabeth Winstead) as a hostage. While McClane distracts Gabriel in conversation, Warlock determines Gabriel's location, at a hijacked NSA building.

McClane and Farrell travel to the NSA building, and the detective combats terrorists while Farrell discovers and tries to undo Gabriel's plan to steal backup financial information from servers in the building. Farrell is able to lock the terrorists out of their server hack, rendering the task incomplete, and then he is taken hostage by the terrorists. With McClane after them, Gabriel and his henchmen flee the building with their hostages. McClane manages to hijack one of the escaping trucks and pursues Gabriel and the hostages. Gabriel renders a hack to deceive the pilot of a F-35 Lightning II jet to attack McClane's truck. The jet engages McClane, destroying much of the freeway in the process, but the detective is able to escape. He tracks Gabriel to a warehouse, where the terrorist is forcing Farrell to undo the encryption at gunpoint. McClane and Farrell are able to kill Gabriel and his men before they force Farrell to decrypt the lock, resolving the crisis. The FBI arrives shortly after to tend to the wounds of Farrell, McClane, and his daughter. The final shot is McClane and his daughter leaving in an ambulance.