The crew of the commercial starship Nostromo, carrying valuable minerals from the far reaches of space is awoken from stasis on a return trip to Earth only to find they have only made half the journey. The ship was stopped in the middle of its journey by the computer's main terminal, Mother, due to receiving a radio interference that the crew are under contract to investigate. But once they locate the source of the signal on an unknown planet, things take a turn for the worst, as each crew member must fight to survive an enemy they know nothing about.