Crew members of a cargo spacecraft answer a distress call from a derelict alien vessel. However, their mission of mercy has fatal repercussions when a deadly, seemingly indestructible monster gets on board their ship and starts killing them one by one. Ridley Scott's sci-fi horror, starring Sigourney Weaver, Tom Skerritt, Ian Holm, John Hurt, Harry Dean Stanton, Yaphet Kotto and Veronica Cartwright.