Previous movies in the "Alien" franchise, particularly Alien³, have established that the Alien creatures take on some physical characteristics of the creatures they gestate inside. This film ends with an alien "chestburster" emerging from inside a Predator; the creature has green coloration, an obvious resemblance to the Predator face, and makes the trademark "clicking" noise.
With the filming of this movie Lance Henriksen became the second actor to be attacked and/or killed by an Alien, A Predator and The Terminator. Bill Paxton was the first.
According to director Paul W.S. Anderson, if they'd filmed in Hollywood, the sets would have cost them $20 million. In Prague, they only cost $2 million, an important factor in keeping the film's budget down below $50 million.
Lance Henriksen was first to be cast to maintain some kind of continuity with the previous films.
The most commercially successful of both Alien and Predator movies, grossing over $172 million.
The Antarctic setting on Bouvet Island is based on the unexplained "Vela Incident" of September 22, 1979, where a satellite recorded a flash of light near the island. It was first speculated to have been a man made nuclear explosion or a natural event such as a meteor strike, but this has never been resolved.
Guillermo del Toro was offered the director's chair but opted to make Hellboy instead.
Not screened for critics.
The animatronic Queen was controlled by a motion-control rig which could save her movements digitally. So, if the Queen made a nice looking move in rehearsal, the move could be replayed verbatim in front of the camera.
The morse code picked up by the satellite at the beginning of the film spells out the words, "Whoever wins, we lose". This is, of course, the tagline used to promote the film.
The green glow stick dropped down the shaft contains the same fluorescent liquid used by the effects departments of all the Predator movies as the Predators' blood. According to Predator director John McTiernan, they stumbled on the effect after unconvincing attempts to make the blood look orange forced the crew to look for alternatives.
When Lex asks Sebastian how to say "scared shitless" in Italian, he replies "Non vedo l'ora di uscire da questa piramide con te, perché mi sto cagando addosso." Translated, this literally means "I can't wait to get out of this pyramid with you, because I'm shitting myself."
The words "alien" and "predator" are never said in this movie. Aliens are called "things", "creatures", and "serpents". Predators are referred to as "hunters" and "humanoids".
The design in the center of the floor of the sacrificial chamber is almost identical to the artwork of the Alien³ poster.
At the beginning of the film, the readout of the Predator ship is shown reflected in the visor of the predator mask, just as in Alien the readouts of the Nostromo were reflected on the space helmets.
In an interview, director Paul W.S. Anderson said that Arnold Schwarzenegger offered to reprise his role as Dutch Schaeffer at the end of this movie as a cameo, but only if he lost the election for California governor.
While this film languished in so-called "development hell" for years, 20th-Century Fox considered producing a fifth film in the "Alien" franchise instead. James Cameron, who wrote and directed Aliens, had written a script and even approached Sigourney Weaver to star and Ridley Scott to direct, both of whom expressed interest. When the studio decided to use the Alien/Predator crossover story instead, Cameron, Weaver and Scott all distanced themselves from the project, and later, declared they would never work on either franchise again.
The first film in the "Alien" franchise to not feature Sigourney Weaver, who has said in interviews the idea of the crossover "sounded awful".
The altars where victims were placed in the Chamber of Sacrifices of the pyramid is arranged identically to the hibernation pods in the original Alien movie.
The scene in which Weyland's team discovers the sacrificial chamber inside the pyramid was originally longer than seen in the theatrical cut. After Rousseau and Thomas discuss the hole in the corpse's chest, Sebastian finds a calcified facehugger. Lex and Sebastian then theorize as to what the creature's origin could be.
The drawings that Paul W.S. Anderson used for his original presentation to 20th Century Fox were done by Patrick Tatopoulos.
At one stage both Peter Weller and Gary Busey were approached to do a cameo as John Yutani, the other founder of the infamous "Weyland-Yutani" Company from the "Alien" films, but Yutani was written out of the script. The character was later used in the sequel, Aliens vs. Predator: Requiem, this time as a female.
The role of Max Stafford was written specifically for Colin Salmon.
The Alien vs. Predator story crossed over virtually all forms of media before becoming a feature film. There was a successful comic book series, toy line, multiple video games, soundtrack, and even a trading card series.
Was rumored to be in development ever since a skull from the title characters in the Alien film series appeared in the spaceship trophy room in Predator 2.
First Predator movie to feature a left-handed predator.