Alien: Romulus might be a standalone entry in the franchise, but it wouldn't hurt to watch these Alien movies before heading into theaters.
Alien: Romulus follows a new set of protagonists in a story set in the year 2142, 20 years after the events of Alien and 37 years before the start of Aliens.
Despite its standalone nature, the horror film is sprinkled with references and Easter eggs tied to what came before.
4 Movies to Watch Before Seeing Alien: Romulus
Alien (1979)
Ridley Scott's Alien is at the top of the list as a must-watch movie before seeing Alien: Romulus, considering that the timeline placement of the latest entry to the franchise is closer to the original (they are only 20 years apart).
Alien introduces Sigourney Weaver's iconic Ellen Ripley as she becomes the lone survivor of the Nostromo ship after her crew dies from an encounter with the Xenomorph.
Ripley ultimately defeats the creature by successfully pushing it into deep space and she goes into stasis as she prepares for a return trip to Earth.
However, Alien: Romulus revealed that the same Xenomorph from Alien is captured and taken in by a science team from Weyland-Yutani Corporation for experimentation, assuming that the creature is dead (spoiler: it is not dead).
The creature awakens and wreaks havoc inside the Renaissance station and it is mainly the one responsible for the plethora of facehuggers and hive of Xenomorphs that are already there by the time Rain and her friends arrive.
Another connection is the return of Ash's likeness into the movie as it is integrated into a similar-looking android named Rook. The character even resembles the late Alien actor Ian Holm with the use of AI augmentation and vocal performance by Daniel Betts.
For those unaware, Ash is the evil android who manipulated the events of Alien which led to the death of Ripley's crew.
Alien: Romulus also brings back the horror vibe of Alien while also using the same in-universe technology from the first movie.
Aliens (1986)
James Cameron's Aliens continues Ellen Ripley's story as she teams up with colonial marines to take out a horde of Xenomorphs on a moon called LV-426.
The sequel introduced the franchise's version of an Alien Queen as well as the iconic weapon used by the colonial marines called Armat M41A Pulse Rifle MK2.
Aliens takes place in 2179, 37 years after the events of Aliens: Romulus.
The movie's notable connection to Aliens: Romulus involves Tyler's mention of colonial marines after they manage to arm themselves with the pulse rifle ahead of their encounter with the horde of Xenomorphs.
Another one is a key piece of dialogue that pays tribute to Sigourney Weaver's iconic line from Aliens where Ripley said, "Get away from her, you bitch," to the Alien Queen that was targeting Newt.
The same line was uttered by Andy (David Jonsson) after shooting a Xenomorph in the head several times while saving Rain in the process.
Prometheus (2012)
Although Prometheus takes place 49 years before the events of Alien: Romulus, it is a worthwhile viewing experience to further understand the lore behind the franchise and the origins of mankind and the Xenomorphs.
In Prometheus, it is revealed that a species called the Engineers were responsible for creating humanity. It also introduced an antagonistic android named David who is hellbent on creating "the perfect organism" which would eventually be the Xenomorphs.
Science officer Rook from Alien: Romulus namedropped the term, "Prometheus 5," during his heavy exposition about unlocking a new form of the black goo that was featured in Prometheus.
The said black goo came from experimenting with the Xenomorph from the first movie and they plan to use it as a cure for novel diseases of humanity.
Some have also pointed out that the human-Xenomorph hybrid that was featured in Romulus' final battle somewhat resembled the bald-headed and pale-skinned design of an Engineer but in a scarier form.
Alien: Covenant (2017)
Another worthy entry to the Alien: Romulus watch list is the sequel to Prometheus: Alien: Covenant.
Taking place in 2104, Alien: Covenant continues David's pursuit of finding ways to produce the perfect organism by using the crew of the Covenant as lab rats combined with the manipulation of the black goo for his own nefarious ways.
Although there are only minimal connections between Covenant and Romulus, the prequel is still worth watching to gain a better understanding of the franchise's world-building elements like the black goo and how an android is willing to go to great lengths to fulfill a flawed mission.
[ Alien Romulus: Biggest Spoilers from Plot & Ending Explained ]
Alien: Romulus is now playing in theaters worldwide.
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