30 Alien facts that will blow your mind

10. Star Beast

The original title Star Beast never sat right with Alien screenwriter Dan O'Bannon. Only when he looked at the script and saw how many times the word alien appeared did he fix on that for the title, as it worked as both a noun and adjective.

9. A different Hicks

James Remar (you know, Dexter's dad) landed the role of Corporal Dwayne Hicks and underwent the extensive Marines training along with his fellow 'grunts' in preparation for Aliens. Two weeks into the shoot due to creative differences or personal reasons - both of which were cited in connection to his departure - he exited the film, leaving James Cameron and his producers in a tight spot.

Due to their positive experience working with him on The Terminator, Cameron and Gale Anne Hurd called up Michael Biehn back in the US (the film was shooting in London) to see if he was interested. He said yes on the Friday, flew out Saturday and started shooting on Monday.

One shot of Remar does remain in the movie. When the Marines first enter the colony's compound the background featured a highly-detailed matte painting that had since been destroyed. Too expensive to recreate once Biehn arrived, they simply kept the shot in along with the sight of Remar's back.

8. Egg chamber

In one of Ronald Shusett and Dan O'Bannon's early Alien drafts, Kane stumbles across the egg chamber in a different location. As the Nostromo crew explore the Space Jockey's ship they spy hieroglyphic imagery etched into the walls, including one that depicts a giant pyramid (and another set that explains the alien's lifecycle). They venture outside and eventually discover the structure - referred to in drafts as a breeding temple - not realising the signage was a caution to stay away.

"The pyramid and derelict [Space Jockey's spacecraft] - two different elements- were still the subject of a see-saw debate when I came on the project," Scott later recalled. "I would love to have shot the pyramid, but the more I thought about it, the more I realized it would have been wonderful in a three-hour version. What finally cracked it was the budget. We just had to get rid of it."

The egg chamber was situated in the Space Jockey's control room instead, and the pyramid later featured in Prometheus.

7. An alternate life for Newt and Hicks

In 1988 Dark Horse Comics published a string of titles to serve as a sequel to Aliens. Ripley features briefly towards the end of the main storyline, which focuses on Newt and Hicks as they take the battle to the xenomorphs' home planet - and discover a beast that even the aliens are afraid of.

While all that's kicking off in deep space, back on Earth an Alien queen is smuggled onto the planet by a scientific corporation intent on breeding xenomorphs for war. A religious sect on Earth who worship the mother set the beast loose and... well, you can imagine what happens next.

Later reprints of the series were retconned to fit into the very different continuity set forth in Alien 3. Hicks and Newt became Wilks and Billie. Just to make things even more confusing, Dark Horse issued another 30th anniversary special of the comics in 2016... returning those names to Newt and Hicks.

6. Resurrection of Ripley

Sigourney Weaver's reluctance to sign up for yet another bug hunt almost led to a completely different character returning from the grave in Alien Resurrection. One of the early outlines penned by Joss Whedon featured Newt. Cloned for her survival instinct, demonstrated by her time on LV-426, Newt was generated in order to track down the aliens for The Company.

Despite Whedon's attempts to push forward, Fox backed down when Weaver agreed to return. After reading the script, the scene in which several earlier botched attempts at cloning piqued her interest.

5. Terminator connection

Preliminary Aliens drafts had Bishop mention that he was created by Cyberdyne Systems - the technology corporation responsible for creating Skynet in the Terminator saga. It was later switched to Hyperdyne.

One element that does remain happens aboard the drop ship. In the special edition, Hudson's "ultimate badass" rant about the Marines' arsenal of weapons, makes reference to a "phased plasma pulse rifle." The weapons the Marines use are in fact, M41A pulse rifles. This line is a cheeky connect between James Cameron's previous film, in which the T-800 asks a gun store clerk for a "phased plasma rifle."

Bill Paxton, who plays Hudson, also appeared in The Terminator as one of the street punks at the observatory.

4. Props to the fans

Even though most shots of it wound up on the cutting room floor, James Cameron still needed to include The Derelict in Aliens - the Space Jockey's donut-shaped aircraft seen in the first film. The crew planned to use the model created for Alien, but later found out Fox no longer owned the piece.

Luckily, an avid fan came to their aid. Bob Burns, who scooped up the piece for his mammoth memorabilia stash, had the original model sat on his driveway for most of the '80s and offered it up to the crew. Likewise for Alien Resurrection, he lent the team the original queen alien's head from Aliens after it was discovered that the moulds had been destroyed.

3. Hello, dolly!

Sigourney Weaver puts in one hell of a performance during the climactic end sequence of Aliens, fighting off the alien soldiers and their queen all while holding a hefty pulse rifle and actress Carrie Henn at her waist.

As the shoot wore on, the weight became exhausting: so a prosthetic was fashioned - that involved the young Henn being swaddled in the makeup chair - that allowed Weaver to carry a lightweight doll replica of Newt as she charged around the compound. You can spot when its Henn and when its the doll, depending on whether or not Newt is facing the camera.

2. All aboard

A now-legendary part of the films, the facehugger concept was ushered in when Alien screenwriters Ronald Shusett and Dan O'Bannon hit a wall figuring out how the creature would make its way aboard the Nostromo.

Shusett cooked up the final idea for the parasite upon waking from a dream. "I have an idea: the monster screws one of them," he said. The pair riffed on the notion of what O'Bannon terms "interspecies alien rape" as a way of injecting fear into moviegoers. Specifically, to stun men in the audience by making the first victim of the creature's invasive impregnation male.

1. Kane's last supper

Ridley Scott deliberately kept the actors off the Alien set while production designers and the effects crew dressed the scene for Kane's last meal. Despite having read the script, none of the principal leads knew what was going to happen. So when the chestburster emerges from John Hurt and a stream of fake blood blasts a stunned Veronica Cartwright, her shocked reaction and scream? Completely authentic.

"Everyone was wearing raincoats," Weaver later recalled. "We should have been a little suspicious."