1. It's Based on a Novel.

Roderick Thorp's 1979 novel "Nothing Lasts Forever."
Source: Amazon
The film is an adaptation of Roderick Thorp's 1979 novel "Nothing Lasts Forever." The book is a sequel to his 1966 novel "The Detective," which was adapted into a 1968 film starring Frank Sinatra.
Due to contractual obligations, the role of John McClane was technically first offered to a then 73-year-old Sinatra, who declined. But it would have been fun to see Old Blue Eyes out there kicking terrorist butt.
2. Bruce Willis Was Far from the First Choice.
Before Bruce Willis was cast as the iconic John McClane, the role was offered to a long list of established action stars, including Arnold Schwarzenegger, Sylvester Stallone, Burt Reynolds, and Richard Gere, all of whom turned it down.
They really wanted an established action star, and at the time, Willis, known for his comedic role in the TV series Moonlighting.
3. It Was Alan Rickman's Feature Film Debut.
The role of the calculating and charismatic villain Hans Gruber was the first feature film role for the late Alan Rickman.
A seasoned stage actor, Rickman's portrayal of Gruber is widely regarded as one of the greatest cinematic villains of all time. He booked the role at 41 years old!
4. The Terrifying Fall Was Real.
In the scene where Hans Gruber falls from Nakatomi Plaza, the look of genuine terror on Alan Rickman's face was achieved by dropping him from a 21-foot-high model on a count of two when he was expecting to be dropped on three.
Rickman was not happy about it, but they got an amazing take.
5. Nakatomi Plaza is a Real Building.

Fox Plaza
Credit: Wikimedia Commons
The setting for the film's mayhem, the fictional Nakatomi Plaza, is actually the Fox Plaza in Century City, Los Angeles.
The building was still under construction during filming, adding a layer of authenticity to the chaotic scenes.
6. An On-Set Injury Led to Hearing Loss for Willis.
During the filming of the scene where McClane shoots a terrorist through a table, the extra-loud blanks used for the effect caused permanent hearing loss in Bruce Willis's left ear.
7. The Famous "Yippee-Ki-Yay" Line Was an Ad-Lib.
One of the most iconic lines in action movie history, "Yippee-ki-yay, motherfucker," was an ad-lib by Bruce Willis. He reportedly said it to make his fellow crew members laugh and never expected it to make it into the final cut.
8. The German Terrorists Weren't All German.
While the villains in the film are German, many of the actors who played them were not. Rickman was British, a few henchmen were Russian, and the rest covered the gamut of ethnicities.
In fact, in the German-dubbed version of the film, the terrorists speak in grammatically incorrect German, which has become a point of amusement for German-speaking audiences.
9. The Director Had a Shakespearean Vision.
Director John McTiernan viewed the story as a modern-day version of Shakespeare's "A Midsummer Night's Dream," where a "prince" (McClane) navigates a chaotic and magical night.
In the film's DVD commentary, McTiernan said, “Eventually, we found a way to think of it as something other than a terrorist incident,” he said. “I had this notion – although I didn't really tell the studio this – that you could turn it into a sort of Shakespearean comedy, that it would become a panorama of the people involved in the incident. I basically structured it as a comedy. It was actually A Midsummer Night’s Dream. That is, something happens on a festival night that turns the world upside-down, and all the princes become asses and all the asses become princes. In the morning, the true lovers are reunited and everyone goes on, but the world is better than it was the night before.”
“So I started making changes in the script along those lines,” McTiernan continued. “I just tried to find ways to expand the comedy and involve other characters. I guess the major change we made was turning it into a robbery, and that was when I said, ‘Yes, I’ll do it.’ As I said, I’ve never found terrorism entertaining, but a good robbery is fun. Whether it be about the bad guys or the good guys, people love to watch a good caper. I thought, ‘If I could put that in the center of it, then it would take away the meanness.’ So many action movies are mean at their heart. I personally find them uninteresting and unentertaining. They’re just no fun.”
10. It's Officially a Christmas Movie (According to the Director).
'Die Hard'Credit: Fox
The long-standing debate about whether Die Hard is a Christmas movie was settled by director John McTiernan, who has stated that he intended for it to be a Christmas film. So that's that, losers.
Summing It All Up
Die Hard is one of my favorite movies of all time. I watch it every Christmas Eve, and I love how, after all these years, people still flock to the movie.
Let me know what you think in the comments.