A commercial spaceship named Nostromo receives a distress signal from a distant planet. Following protocol, the ship's crew, led by the greedy and cowardly Kane, intercepts the signal where they unexpectedly discover thousands of alien eggs inside a mysterious chamber. An embryo-like creature attacks one of the crew members, implanting a parasitic alien inside its victim before birthing itself from its host. The newly born creature escapes and hides aboard the Nostromo, tormenting the dwindling crew with its violent, alien instincts