One year after his heroics in Los Angeles, John McClane is an off-duty cop who is the wrong guy in the wrong place at the wrong time. On a snowy Christmas Eve, as he waits for his wife's plane to land at Washington Dulles International Airport, terrorists take over the air traffic control system in a plot to free a South American army general and drug smuggler being flown into the US to face drug charges. It's now up to McClane to take on the terrorists, while coping with an inept airport police chief, an uncooperative anti-terrorist squad, and the life of his wife and everyone else trapped in planes circling overhead.

After escaping a calamitous train crash, Ethan realizes The Entity is stashed aboard an old Russian submarine, but a foe from his past named Gabriel is also on the trail.