By that time, O'Bannon, who had grown up a science fiction enthusiast in St. Louis, had abandoned technical work (including a stint as a computer animator on George Lucas' 1977 classic "Star Wars") for screenwriting. Together with Ronald Schusett, he devised the original story for "Alien" (1979), a graphic, gory feature whose story is rooted in sci-fi adventures. The story is fairly simplistic and formulaic: a spaceship is forced to land on a hostile planet where a parasitic creature finds a host in one of the crew members. It is up to the rest, particularly Sigourney Weaver's Ripley, to fight the alien. Owing much to films like "It! The Terror From Beyond Space," "Alien" benefited from its strong female lead and director Ridley Scott's visual stylings. O'Bannon has been very vocal in his complaints over the various rewrites (by Walter Hill and David Giler) the script underwent. Despite the author's unhappiness, Twentieth Century Fox benefited, and the film has spawned three sequels of varying quality.O'Bannon has also voiced his displeasure with his next big-budget outing, John Badham's "Blue Thunder" (1983), an action yarn about an L.A. helicopter surveillance team. Originally written with Don Jakoby, "Blue Thunder" also underwent extensive rewriting, diluting some of its political content. He and Jakoby scripted "Lifeforce" (1985), a bizarrely fascinating tale that veers from alien visitation to vampirism to an apocalyptic ending that was helmed by Tobe Hooper. The trio further collaborated on the 1986 remake of "Invaders From Mars," which most critics felt was inferior to the original. He and Schusett reteamed on "Total Recall" (1990), an adaptation of the classic Philip K Dick short story "We Can Remember It for You Wholesale." Blessed with the presence of Arnold Schwarzenegger and Paul Verhoeven's sure-footed direction, the film went on to earn well over $100 million. He went on to co-write "Screamers" (1995), about post-apocalyptic robots programmed to kill, adapted from another Dick story, "The Second Variety."In the mid-80s, O'Bannon moved to the director's chair with "Return of the Living Dead," an uneven but highly entertaining follow-up to George Romero's 1968 cult classic "Night of the Living Dead." Beginning as a spirited comic spoof of zombie films, the film turns seriously violent with an unsatisfying anti-climactic ending. (Nevertheless, it was popular enough to warrant two sequels, although O'Bannon was not involved in either.) His second feature, "The Resurrected" (1992), was released directly on video and focused on a family's ancient rituals which awaken the dead.