On Christmas Eve 1990, off-duty police detective John McClane was in the aiport waiting to pick up his wife Holly when he sees some suspicious men in the airport lounge. He follows them to the airport luggage access area and sees two of them doing something to the control penal near one of the airport's conveyor belt. Then a shootout occurs, which McClane killed a mercenary named Oswald Cochrane. but the other mercenary, Miller got away.
When the cops were called off from the crime scene, McClane goes to see the airport police chief, Captain Carmine Lorenzo about it. The stubborn Lorenzo believes that the guys that McClane went after were just a bunch of punks trying to steal luggage and refuses to listen to McClane's thoughts about the people are professionals. Lorenzo removes him from his office.
Then McClane conducts his own investigation and takes Cochrane's fingerprints. Then he calls Al Powell to help identify the man he killed with the fingerprints he placed in the piece of paper and faxed it over to him. Powell then calls him back. He tells McClane that Cochrane was reported to be killed in a helicopter accident when he was an American military advisor in Honduras two years before. Then McClane heads up for the airport's control tower. AS he entered the control tower, Lorenzo tells the tower is restricted area, but Trudeau the chief of air operations, overrides Lorenzo as he wants to know what's going on. He reveals Cochrane's dossier to them. As McClane reveals about his suspicion that someone will likely hit the airport and that the man he killed is a professional mercenary, not someone stealing luggage.
Then the airport's control tower is hijacked by rogue military officer Colonel Stuart and his band of terrorists who shut off the landing lights, leaving the confused planes circling overhead because their visibility is clouded by a snowstorm.
McClane finds himself in a race against time to stop the terrorists before his wife's plane and several other incoming flights that are circling the airport run out of fuel and crash. McClane kills all of the mercenaries and thwarts their plan by blowing up their getaway plane, finally providing a landing light for all of the airplanes and he and Holly are united.
- Filming of Die Hard 2 never took place in Dulles. The stand-ins were the now-closed Stapleton International Airport in Denver and a few scenes at Los Angeles International Airport (LAX).