With a sleek style and a sharp twist on the “humanity vs. machines” plot, 1999’s The Matrix cemented itself as one of the most important sci-fi movies of the decade. The story laid down by the Wachowskis was perfect for an ongoing franchise, and it soon expanded into video games, anime, and comics. Then, in 2003, the original film was followed by two sequels: The Matrix Reloaded and the storyline’s grand finale, The Matrix Revolutions.

In the end, the trilogy went on to gross well over $1.5 billion at the worldwide box office and helped inspire a new generation of sci-fi movies in the process. Find out more about the creation of the franchise’s swan song as we look at 15 facts about The Matrix Revolutions on its 15th anniversary.

1. THE MATRIX RELOADED AND THE MATRIX REVOLUTIONS WERE SHOT BACK-TO-BACK.

In order to save on massive production costs, Warner Bros. didn’t take a break between the filming of the second and third Matrix movies. Not counting pre- and post-production time, 270 days were spent shooting the two films.

2. THE NAME OF THE MOVIE WASN’T DECIDED UNTIL AFTER SHOOTING.

The temporary production name of the movie was Burly Man.

3. AS A MARKETING STRATEGY, THE MOVIE WAS RELEASED WORLDWIDE AT THE EXACT SAME TIME.

It came out simultaneously in more than 50 countries, premiering at 6 a.m. in Los Angeles, 9 a.m. in New York City, 2 p.m. in London, 5 p.m. in Moscow, 11 p.m. in Tokyo, and so on.

4. THE FILM WOULDN’T HAVE BEEN POSSIBLE WITHOUT A LOT OF MOVIE MAGIC.

In addition to cutting-edge CGI technology, the production included the use of some impressive miniatures, such as the dock door of Zion, which was a 1/10th-scale model. Still, the scale of the door was astonishing as this "miniature" was 30 feet high and 40 feet wide.

5. THE PRODUCTION TOOK ITS RESEARCH TO NEW HEIGHTS.

In order to reference what fighting in zero gravity would look like for the movie’s final fight, the filmmakers actually shot screen tests with stuntmen on reduced gravity airplanes. No actual zero-G footage was used in the final film.

6. NEW TECHNOLOGY WAS CREATED FOR THE FIGHT SCENES.

A custom telescoping rig called the “Tuning Fork” was created to enable one or two stuntmen to twirl multiple times in mid-air while fighting one another.

7. AN UNTIMELY DEATH ALTERED THE SCRIPT.

Jasin Boland , Warner Bros. Entertainment

Gloria Foster, the actress who played the Oracle in the first and second movies, passed away while shooting the third film. She was replaced by actress Mary Alice and the change was added to the plot of the movie.

8. R&B SINGER AALIYAH WAS ORIGINALLY SUPPOSED TO PLAY ZEE.

In another tragic turn of events, the character Zee was recast after Aaliyah, who shot small portions of the role for the second movie, died in a plane crash in 2001. Nona Gaye, daughter of singer Marvin Gaye, ultimately played Zee.

9. CAPTAIN MIFUNE’S NAME IS A NOD TO TOSHIRO MIFUNE.

Toshiro Mifune’s samurai movies (Seven Samurai, Yojimbo, etc.) were major inspirations for the Wachowskis while making the Matrix trilogy, so to honor him, the character Mifune was created.

10. THE ARMORED PERSONNEL UNIT DESIGNS WERE MODELED AFTER GORILLAS.

Though most of these mechanized walkers were CGI, one 14-foot-tall practical APU was built for the movie. It was so big, a crane had to bring it through the back of the set where it was then fully assembled.

11. THE DESIGN OF THE MACHINE CITY WAS INSPIRED BY CORAL REEFS.

The thousands of machine inhabitants were meant to look like crustaceans.

12. THE WACHOWSKIS TURNED TO FAMILY IN DESIGNING THE DEUS EX MACHINA.

Warner Bros. Entertainment

The “God Machine” face was modeled after the Wachowskis’s own infant nephew. The child was filmed performing a number of facial expressions, and the sentinel swarms were then animated to recreate them for the character Deus Ex Machina. The character was voiced by Kevin Michael Richardson.

13. ALL THE SHIP INTERIORS WERE SHOT ON A SINGLE SET.

Only the cables and hardware were changed to differentiate the ships.

14. A NEW SOUND EFFECTS LIBRARY WAS CREATED SPECIFICALLY FOR THE MOVIE.

The fighting sound effects were taken from recording sessions featuring two jiu-jitsu pros sparring with each other.

15. SOME OF THE EXTRAS IN THE FINAL FIGHT SCENE WERE REAL DUMMIES.

The close-up shots of the Agent Smiths looking on during the climactic fight are a mixture of 100 dummies and 50 extras wearing suits and specially molded masks all made to look like actor Hugo Weaving.