In the distant future, during her return to Earth, the commercial spaceship Nostromo intercepts a distress call from a distant moon. The seven-member crew are awakened from hypersleep and the spaceship subsequently descends on the moon. While exploring the moon, a three-member team of the crew discover a derelict spaceship and a huge chamber inside her containing thousands of eggs. When a curious team member goes near the egg, the parasite inside the egg attacks him, rendering him unconscious. He is brought back aboard and the spaceship takes off. After a little while, the parasite dies and his host wakes up seemingly unruffled. Everything soon returns to normal, but not for long.