New York City Detective John McClane (Bruce Willis) arrives in Los Angeles to spend the Christmas holiday with his estranged wife (Bonnie Bedelia). But as McClane waits for his wife's office party to break up, terrorists take control of the building.

While the terrorist leader, Hans Gruber (Alan Rickman) rounds up hostages, McClane slips away unnoticed. Armed with only a service revolver and his cunning, McClane launches his own one-man war.