Template:Alien synopsis

Somewhere in the Zeta 2 Reticuli system, the commercial towing vehicle the USCSS Nostromo edges through space. The onboard computer system activates and awakens the ship's crew members from their cryosleep. The crew consists of Captain Dallas, First officer Kane, Science Officer Ash, Warrant Officer Ellen Ripley, navigator Lambert and engineers Parker and Brett. They sit around a meeting table sharing food and coffee. Parker and Brett complain about their wages and make a point of noting that they are not receiving the same shares as the rest of the crew. Dallas goes to the computer mainframe to check on "Mother". He discovers that the crew has been awakened early due to an ambiguous distress beacon that Mother picked up. The rest of the crew try to get their bearings and they find that they are still in the Outer Rim - a long way from Earth. Ripley tries to send a message to Antarctica Traffic Control, but receives nothing. Dallas joins them on the bridge of the ship and tells them that Mother intercepted a transmission of "unknown origin". As per her programming, she awakened the crew so that they can investigate. They analyze the signal and find that it is an acoustical beacon originating from a planetoid some distance away.

The Nostromo crew approach one of the moons orbiting the planetoid and descend to the surface using one of their drop-ships. Intense winds buffet the ship and they make an extremely shaky landing that sends shockwaves throughout the craft. The ship suffers some structural support and the engineering crew estimate that it will take some seventeen to twenty-five hours to affect repairs.

They determine that the source of the beacon originates some 2,000 meters away from their location. Brett and Parker stay on the ship to make repairs as do Ripley and Ash. Dallas leads Kane and Lambert onto the surface in survival suits. They track the signal to a partially buried derelict ship, which they imagine has been here for thousands of years. They descend into a tunnel running beneath the ship's hull and find a vast corridor with walls that look the vertebrae of some gigantic monster. Upon finding the bridge of the ship, they find the fossilized remains of an alien pilot. The creature is more than fifteen feet in height and seems as if his body is literally growing from his seat. Dallas observes an open chest cavity with its ribs protruding outward as if he were attacked from within or from behind by a large object.

Kane investigates the lower cargo hold of the ship and comes upon a cavern containing a bed of large, leathery eggs. The eggs are set up side by side inside this de facto nursery and a thin, illuminated layer of mist covers them like a blanket. The mist reacts to Kane's presence, but he continues to inspect the eggs. Once he is within close proximity, an aperture on an egg opens and a small, spider-like creature leaps forward and attaches itself to Kane's helmet. Dallas and Lambert hear Kane's screams over their com system and rush to get him back aboard the ship.

Dallas orders Ripley to open the air lock to admit them, but Ripley refuses to do so. She cites quarantine procedures and warns Dallas that she risks endangering the entire crew if she lets Kane on board. Science officer Ash countermands Ripley's directive and lets the crew into the ship. Kane is immediately taken to the infirmary.