Ellen Ripley is sent back to the planet LV-426 to establish contact with a terraforming colony. Once there, she encounters the Alien Queen and her offspring and has to fight them to survive.

In deep space, the crew of the commercial starship Nostromo is awakened from their cryo-sleep capsules halfway through their journey home to investigate a distress call from an alien vessel. The terror begins when the crew encounters a nest of eggs inside the alien ship. An organism from inside an egg leaps out and attaches itself to one of the crew, causing him to fall into a coma.