Ripley, a pilot officer, hibernates inside a spacecraft as it docks at Gateway space station. Later, when Ripley wakes, an employee of the “Company” named Carter Burke explains that she was in “hypersleep” for fifty-seven years. At a Company board meeting, Ripley is interrogated about her decision to destroy a $42 million starfreighter. Although Ripley claims she blew up the ship to annihilate the alien that killed her crew, the flight recorder does not corroborate her explanation, and the board is skeptical. Ripley says the alien, which gestates inside human bodies, laid thousands of eggs on the spaceship after it landed on the planet LV-426. When Ripley’s case is closed, she suggests that chairman Van Leuwen send a mission to LV-426 for proof, but he tells her that settlers have populated the planet for twenty years, developing atmospheric processers, and they have never encountered aliens. Sometime later, Burke tells Ripley that the Company has lost contact with the LV-426 colony and asks her to return to the planet with a brigade of marines. Although Ripley initially refuses, she wakes from a recurring nightmare and calls Burke to agree under the condition that the aliens are annihilated, not retained for research. Later, the rescue mission crew, including Ripley and Burke, approach LV-426 and are awakened from hibernation. During their briefing about the mission, the marines are eager for an alien “bug hunt,” but Ripley warns about the impending danger. The crew is dropped to the surface of LV-426 in a transport spaceship furnished with weapons and an armored vehicle. As they approach the deserted central atmospheric processing plant, Burke informs Ripley that the Company has made a vast investment in the planet’s industry. Heavily armed, the first squad of marines, including Private Vasquez, Private Hudson, Corporal Hicks and Sergeant Apone, enter the building as Ripley surveys video footage transmitted by eye-level cameras attached to their helmets. The soldiers soon find evidence of aliens, but Hicks fails to detect signs of life in his motion sensor. Despite Ripley’s warning, Lieutenant Gorman determines the aliens are gone and commands the remaining crew to enter the building. Inside, they find a “medlab” with aliens preserved in glass. When motion is detected outside, the soldiers prepare for an attack, but instead discover a frightened little girl named Newt. Back in the medlab, Bishop dissects an alien while Hudson detects a congregation of life forms at a nearby processing station. After driving the armored vehicle to the site, a team of marines, including Vasquez, Hudson, Hicks and Apone, find the building covered in a “secreted resin” and soon discover human bodies embalmed within it. One woman, still alive, begs to be killed as an alien bursts from her chest. As Hudson detects another alien, the soldiers are attacked and their communication with Gorman is cut off. Frustrated by Gorman’s incompetence, Ripley takes control of the vehicle and narrowly rescues the few surviving soldiers: Hicks, Hudson and Vasquez. Meanwhile, Gorman hits his head and becomes unconscious. Ripley suggests that they incinerate the planet with a nuclear explosion, but Burke refuses to authorize the plan. When Ripley points out that the mission is a military operation and Hicks is in charge, the corporal orders immediate evacuation and destruction of the plant. Before they can return to the transport spacecraft, however, the ship is attacked by an alien and explodes, leaving the crew stranded. Back at the central plant, Ripley learns it will take seventeen days for a rescue mission to reach them and orders Hudson to find blueprints of the building so they can barricade themselves. Reviewing the plans, the team discovers that aliens are moving from the processing station to the plant through a service tunnel and, after welding the tunnel door shut, Hicks gives Ripley a wristband “locator,” so he can remotely detect her. That night, Ripley puts Newt to sleep in the medlab and gives her the locator, promising not to leave without her. When Bishop tells Ripley about his research, she orders him to kill the alien specimens, but he reports that Burke wants the creatures returned to Company labs alive. Later, Burke explains that the specimens are highly lucrative. Opposing his plan, Ripley says the colony log revealed Burke’s willful neglect to warn settlers about the danger on LV-426 and threatens to implicate him in their deaths. Later, Bishop, an android crew member, shows Ripley and Hicks a malfunctioning ventilation system that will cause the planet to explode in four hours. In a last chance for survival, Bishop offers to commandeer a nearby transmitter so he can remote-pilot a rescue spaceship. After Gorman revives from his injury, Ripley falls asleep with Newt in the medlab, but wakes to find an escaped alien locked inside with them. When Ripley motions for help on the security camera, Burke turns off the monitor. Ripley then uses her cigarette lighter to trigger the fire alarm and as she fights off the alien, Hicks smashes through the window to rescue her. Ripley tells the crew that Burke released the aliens so they would impregnate her and Newt, thereby allowing him to smuggle embryos back to Gateway. Although Hicks wants to kill Burke, the lights go out and Ripley announces that the aliens have cut off the electricity. Using a motion sensor, Hudson detects approaching aliens, and the creatures attack from the ceiling. A battle ensues, leaving Hudson and Burke dead. Following Newt’s directions, the crew escapes through air ducts and Hicks receives a report from Bishop that the rescue ship will land in sixteen minutes. Meanwhile, Vasquez, who is defending the team from behind, is injured and Gorman runs to her aid. Realizing he and Vasquez are surrounded, Gorman detonates a grenade, sacrificing their lives to help the others. Further along in the duct, Newt falls down a shaft and Ripley and Hicks follow the signal from her locator. However, before they rescue Newt, an alien captures the girl and Hicks is wounded. As Ripley helps Hicks to the dock, the spacecraft arrives. Ripley orders Bishop to pilot the ship back to the processing plant where the settlers’ bodies were discovered, convinced that it contains the queen alien’s nest and that Newt is still alive within it. With only minutes to spare before the planet explodes, Ripley follows the locator’s signal into the alien nest but only finds the detached wristband until Newt screams for help. After peeling the girl from the resin, Ripley encounters the queen alien, laying eggs. Ripley backs away, setting fire to the nest. As the queen pursues them, Ripley and Newt return to the dock only to find the ship gone. However, Bishop pilots the spacecraft back to his companions and they escape LV-426 as it explodes. Back at the space station, as Ripley commends Bishop, he is impaled and torn in half by the alien queen, who attached herself to the spaceship as it flew away. Unarmed, Ripley attempts to distract the alien from Newt, then fights the creature by operating a human-shaped mechanical loader. Grabbing the alien with the loader’s arm, Ripley tries to throw the beast into an airlock chamber to eject it from the spaceship, but the alien pulls Ripley inside with her. As Ripley climbs out, she opens the outer door of the chamber and the alien is sucked into space. Later, the three survivors, Hicks, Newt and Ripley, hibernate peacefully as the spaceship returns home.