Alien - Watch Order: Release Order
The Alien franchise explores humanity's terrifying encounters with a perfect killing organism across centuries of space exploration, beginning with Ridley Scott's 1979 masterpiece that redefined science fiction horror. This release order preserves the intended viewing experience as audiences originally encountered the films, allowing the franchise's evolution from pure horror to action-horror hybrid to prequel mythology to unfold naturally.
The watch order avoids spoilers that prequels might reveal about the xenomorphs' origins and lets you experience the franchise's creative journey from the claustrophobic terror of the original through the expanded universe exploration of later entries.

Alien
During its return to the earth, commercial spaceship Nostromo intercepts a distress signal from a distant planet. When a three-member team of the crew discovers a chamber containing thousands of eggs on the planet, a creature inside one of the eggs attacks an explorer. The entire crew is unaware of the impending nightmare set to descend upon them when the alien parasite planted inside its unfortunate host is birthed.

Aliens
Ripley, the sole survivor of the Nostromo's deadly encounter with the monstrous Alien, returns to Earth after drifting through space in hypersleep for 57 years. Although her story is initially met with skepticism, she agrees to accompany a team of Colonial Marines back to LV-426.

Alien³
After escaping with Newt and Hicks from the alien planet, Ripley crash lands on Fiorina 161, a prison planet and host to a correctional facility. Unfortunately, although Newt and Hicks do not survive the crash, a more unwelcome visitor does. The prison does not allow weapons of any kind, and with aid being a long time away, the prisoners must simply survive in any way they can.

Alien Resurrection
Two hundred years after Lt. Ripley died, a group of scientists clone her, hoping to breed the ultimate weapon. But the new Ripley is full of surprises … as are the new aliens. Ripley must team with a band of smugglers to keep the creatures from reaching Earth.

Prometheus
A team of explorers discover a clue to the origins of mankind on Earth, leading them on a journey to the darkest corners of the universe. There, they must fight a terrifying battle to save the future of the human race.

Alien: Covenant
The crew of the colony ship Covenant, bound for a remote planet on the far side of the galaxy, discovers what they think is an uncharted paradise but is actually a dark, dangerous world.

Alien: Romulus
While scavenging the deep ends of a derelict space station, a group of young space colonizers come face to face with the most terrifying life form in the universe.
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