Alien is a 1979 science-fiction horror film directed by Ridley Scott, and starring Sigourney Weaver, Tom Skerritt, Veronica Cartwright, Harry Dean Stanton, John Hurt, Ian Holm and Yaphet Kotto. The film's title refers to a highly aggressive extraterrestrial creature that stalks and attacks the crew of a spaceship. Dan O'Bannon, drawing upon previous works of science fiction and horror, wrote the screenplay from a story he co-authored with Ronald Shusett. The film was produced by Gordon Carroll, David Giler and Walter Hill through their company Brandywine Productions, and was distributed by 20th Century Fox. Giler and Hill revised and made additions to the script. Shusett was executive producer. The eponymous Alien and its accompanying elements were designed by the Swiss artist H. R. Giger, while concept artists Ron Cobb and Chris Foss designed the more human aspects of the film. Alien began a franchise: it has three sequels, and two prequels.