Trivia: During filming, Alan Rickman was found proficient at mimicking American accents; the scene in which McClane and Hans Gruber meet was then inserted.
Trivia: One cop says that John McClane (Bruce Willis) "could be a f***ing bartender for all we know". Prior to becoming a well-known actor, Willis was a bartender.
Trivia: Bruce Willis was only fifth choice for the role of John McClane. The others were, in order: Arnold Schwarzenegger, Sylvester Stallone, Burt Reynolds, and Richard Gere.
Trivia: The film was originally planned as a vehicle for Arnold Schwarzenegger and a sequel to Commando, but Arnie declined.
Trivia: When Bruce Willis (well, the stuntman) misses one of the vents in the elevator shaft, this was unintentional. John McTiernan left it in to give viewers a little scare.
Trivia: At the end, Karl emerges from the building and tries to kill McClane, only to be gunned down by Powell. The triumphant music which swells as Powell shoots him is from the "Aliens" score--it plays at the end of that movie when Bishop reappears in the dropship to save Ripley and Newt, after they think he's abandoned them.
Trivia: For the shot where Hans Gruber falls from the top of the building, Alan Rickman was dropped by a stuntman from a 20-foot high model onto an air bag. To get the right reaction, the stunt man dropped Rickman on the count of two instead of three.
Trivia: Die Hard and Die Hard 2 are based on books by separate authors, "Nothing Lasts Forever" by Roderick Thorp and "58 Minutes" by Walter Wager, which share none of the same characters. In both books, it is the hero's daughter that is in peril rather than his wife, and the hero is also more trusted by the authorities than McClane. (In "Nothing Lasts Forever," he tosses his wallet out the window so the police on the ground know he's a cop.).
Trivia: Regarding a previous Trivia entry: in the German version, ALL German terrorists received Anglicized names, and their background was altered as well. This was due to terrorist activities in Germany - the kidnapping of an airplane in Landshut (1977) and the activities of the Rote-Armee-Fraktion ('Red Army Fraction') in the Seventies -; the German producers evidently felt uncomfortable about the idea of having German terrorists appear in foreign movies also.
Trivia: The scene where Alan Rickman and Bruce Willis meet atop the Nakatomi Tower was completely unrehearsed. This was done in order to create a greater feeling of spontaneity between the two men.
Trivia: Bruce Willis ad-libbed his dialogue in the scene where John McClane is pulling the glass out of his feet.
Trivia: Bruce Willis lost two-thirds of his hearing in his left ear after firing a gun loaded with extra loud blanks from underneath a table in the scene before he throws the dead terrorist onto Al's car.
Trivia: The terrorists show up at Nakatomi Plaza in a truck marked "Pacific Courier" (except Karl and Theo, who arrive by car). This fictional company name also appears on the side of the plane the bus crashes into at the end of "Speed." Jan de Bont, who directed "Speed," was DP on "Die Hard."