Die Hard 4.0 (2007)

Live Free or Die Hard (released as Die Hard 4.0 outside North America) is a 2007 American action thriller film and the fourth installment in the Die Hard film series. The film was directed by Len Wiseman and starred Bruce Willis as John McClane. The film's name was adapted from New Hampshire's state motto, "Live Free or Die". In the film, McClane attempts to stop cyber-terrorists who hack into government and commercial computers across the United States with the goal of starting a "fire sale" that would disable key elements of the nation's infrastructure. The film was based on the 1997 article "A Farewell to Arms" written for Wired magazine by John Carlin.

Live Free or Die Hard was released in the United States on June 27, 2007. The film earned total international box office gross receipts of $383.4 million, making it the highest-grossing film in the Die Hard series. It received generally positive reviews from critics, who called the film a return to form for the Die Hard series. It is the only Die Hard film to be theatrically released with a PG-13 rating from the MPAA. A fifth film, A Good Day to Die Hard, was released in 2013.

The FBI responds to a brief computer outage at its Cyber-Security Division by tracking down top computer hackers. The FBI asks New York City Police Department detective John McClane to bring in hacker Matthew "Matt" Farrell. McClane arrives at Farrell's residence just in time to save Farrell from assassins sent by Mai Linh, who works for Thomas Gabriel.

On the way to Washington, D.C., Farrell tells McClane that he had written an algorithm for Linh that could crack a specific security system for white hat purposes. Meanwhile, Gabriel orders his crew of hackers to take control of transportation grids and the stock market, while also nationally broadcasting a message threatening the United States. Farrell recognizes this as the start of a "fire sale", which is a cyber attack designed to disable the nation's infrastructure. McClane and Farrell are driven to FBI headquarters, but Linh poses as a dispatcher and reroutes the convoy into the path of an assault helicopter. McClane fends off the attackers and destroys the helicopter by launching a car into it.

Gabriel initiates a second broadcast showing a simulated explosion of the U.S. Capitol, causing a public panic. Farrell guesses that Gabriel's next target is the power grid, and he and McClane drive to a utility superstation in West Virginia. They find a team led by Linh taking over the superstation. McClane and Farrell kill the team, and Linh falls to her death following a struggle with McClane. Enraged over Linh's death, Gabriel redirects large amounts of natural gas to the utility superstation in an attempt to kill McClane and Farrell, although they are able to escape.

McClane and Farrell then travel by helicopter to the home of hacker Frederick "Warlock" Kaludis. Warlock identifies the piece of code Farrell wrote for Linh as a means to access data at a Social Security Administration building at Woodlawn, Maryland. Warlock tells McClane and Matt that Gabriel was a top security expert for the U.S. Department of Defense. Gabriel attempted to alert the Department to weaknesses that made America's network infrastructure vulnerable to cyberwarfare, but his unorthodox methods led to his dismissal. Warlock runs a traceroute and identifies Gabriel's location. Gabriel taps into their connection and reveals that he has located McClane's estranged daughter, Lucy. McClane obtains an image of Gabriel which he relays to the FBI. It is revealed that the Woodlawn building is actually an NSA facility intended to back up the nation's personal and financial records in the event of a cyber attack. Gabriel's attack on the FBI prompted a download of financial data to Woodlawn. Access to that data would allow Gabriel to siphon off large amounts of money and disappear without a trace. Lucy is kidnapped by Gabriel.

McClane and Farrell race to the Woodlawn facility, where Farrell discovers that Gabriel's men are downloading financial information. He manages to encrypt the data before he is captured. McClane kills more of Gabriel's henchmen. Gabriel then takes Farrell and Lucy with him as his team flees. McClane pursues Gabriel, hijacking the semi Gabriel used to conduct the firesale hacking. Gabriel accesses the communication system of a F-35B Lightning II and, impersonating the flight controller, orders the pilot to attack the truck McClane is driving. McClane manages to destroy the fighter jet, the pilot ejecting, then makes his way to a nearby warehouse. There, Gabriel demands that Farrell de-encrypt the financial data; when Farrell refuses, Gabriel shoots him in the knee and threatens to kill Lucy if he does not comply. McClane arrives and kills two of Gabriel's henchmen, but the final remaining henchman, Emerson, shoots him in the right shoulder and Gabriel holds him at gunpoint.

Gabriel positions himself behind McClane, putting the barrel of the gun in his shoulder wound. McClane then pulls the trigger. The bullet travels through McClane's shoulder and hits Gabriel in the chest, killing him. Farrell grabs a handgun and kills Emerson. Afterwards, McClane thanks Farrell for saving Lucy's life.