Often imitated but never duplicated, Ridley Scott's Alien is one of the best sci-fi horror films ever made. The movie has inspired several sequels and at least one spin-off franchise, making it one of Fox's biggest cinematic properties.

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As the original Alien celebrates its 40th anniversary this year, a new documentary called Memory: The Origins of Alien has just been released. Before you check it out, we have a double-fistful of cool factoids and tidbits about Ridley Scott's groundbreaking original. In fact, we've added a few more to this list to round out a total of fifteen.

Updated on November 5th, 2020 by Derek Draven: Alien has proven to be a film that's littered with a plethora of hidden details and references. As discussed in the updated intro, we've added more facts about the fine details of Alien that fans might have missed. Some are subtle, while others require some explanation in order to give a proper context. 

A Real Star System

Alien star system

At the beginning of the film, the Nostromo crew awakens from hypersleep believing they're well on their way back to Earth. However, they quickly learn that their stasis was interrupted under official company orders to investigate a distress beacon on a remote world.

Lambert mentions that the Nostromo is just short of Zeta 2 Reticuli, which is actually a real dual-star system. It would take thirty-nine light-years to reach from Earth, making it one of the closest in proximity to our own solar system.

The Song That Cost A Fortune

Ellen Ripley in Alien

Every Alien fan re that bone-chilling scene where they learned that the alien had stowed away on board Ripley's EEV before the Nostromo went nova. To date, it boasts one of the most effective jump scares in horror movie history, as well as tension ratcheted up to head-bursting levels.

Sigourney Weaver ad-libbed a small but important part of the scene when she begins nervously singing "You Are My Lucky Star" to herself. Scott wanted to keep the scene intact, but the studio was enraged when they learned just how expensive the rights were to use it.

Yaphet Kotto Trolled Sigourney Weaver

Sigourney Weaver in Alien

Ridley Scott was keen on extracting as much out of his actors as possible, and that meant doing things that would never be permitted on today's over-legalized movie sets. He would frequently pit one actor against another without them knowing so as to get a natural reaction, such as a scene in the Director's Cut where Veronica Cartwright slaps Sigourney Weaver across the face.

It wouldn't be the last time Scott pulled a stunt like this. After Dallas' death scene, Scott told actor Yaphet Kotto to purposely goad Sigourney Weaver during an ad-libbed scene which caused her to scream at him in anger. The emotion is very real and was exactly what Scott was hoping to capture on film.

Space Rock Lights

The alien egg hive

In order to duplicate the thin layer of blue mist that covered the egg chamber deep inside the bowels of the derelict, Ridley Scott had to come up with something convincing besides a simple blue light. He wanted something with a texture that felt like an actual material as opposed to just a shining color.

According to legend, famous rock band The Who were hanging out in the sound stage next door to the Alien set in order to try out laser lights for their live shows. Scott borrowed the lasers to get the shot which added another degree of mystery to the scene.

Oysters RockaFacehugger

Facehugger autopsy in Alien

With limited resources and a lack of materials to create a set of convincing extraterrestrial innards, Ridley Scott relied on a sheep kidney, shellfish, and four oysters to simulate the internals of the facehugger. While the effect is quite obvious today, it must have seemed quite convincing in 1979.

Those who have worked on a studio set know how hot the lights can get, and this needed to be taken into when filming since the intense heat would cause the food to go off rather fast. Rest assured, nobody wanted to stick their nose close to such an offensive smell.

Ash Never Eats

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One of the biggest surprises in Alien is the revelation that Ash is an android. But if you pay close attention to Ash's diet, you might notice the foreshadowing of his true character.

During the early breakfast scene, Ash can be seen reaching out for a box of cereal. However, we never seem him take a bit of food throughout the movie. The only thing Ash actually consumes is a white milky substance, which resembles his blood when his robotic body is disassembled in the end.

Upside Down Egg Shot

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During the scene right before the "face-hugger" first appears, a shot filmed upside down can be detected.

Just as the Nostromo crew inspects the Alien eggs, the slime on the shell begins to drip upwards rather than downwards. Director Ridley Scott did this on purpose by hanging the egg from the ceiling and flipping the camera upside down. The result has a disorienting, otherworldly effect on the viewer. Yet, it happens so fast that the effect is subliminal.

Blade Runner Connection

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Ridley Scott has publicly gone on record stating that Alien and his movie Blade Runner share the same cinematic sci-fi universe. Well, if you look closely, visual evidence in Alien can be found to this claim. How many of you have ever noticed this?

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When Ripley enters the shuttle ignition phase, she stumbles past a monitor that displays a screen labeled as "Environmental CTR Purge." Three years later, the same visual display would appear in Blade Runner when Deckard is transported to visit Bryant via flying police vehicle. Great Scott!

Gastronomy

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While some of the most otherworldly parts of the film relate to alien anatomy, it was exotic food ingredients from Earth that were used to create such. But you'd never know by looking at them.

For example, the interior of the alien eggs was comprised of cow hearts and stomachs. Additionally, the tubes through which the "face-hugger" implants eggs were made of sheep intestine. But that's not all. For the inside of Ash's robotic head, spaghetti, inexpensive caviar, and onion rings were used. Yum! Now, who's hungry?

Mid-Credit Sound FX

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Alien is scary enough to send you running for the hills immediately after it's over. But if you stick around for a few minutes, you'll get one last chill.

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As soon as the film ends and the credits begin to roll, turn up the volume as loud as you can. After a few seconds, you can hear the unsettling sound of a pod opening. What's extra unnerving is the sound resembles both an alien pod opening as well as the Nostromo crew's cryo-pod. Does the sound signify Ripley's safe return to Earth, or does it suggest something far more sinister?