'Alien' is a 1979 science-fiction horror film directed by Ridley Scott. Based on a story by O'Bannon and Ronald Shusett, it follows the crew of the commercial space tug Nostromo, who encounter the eponymous Alien, a deadly and aggressive extraterrestrial set loose on the ship. The film stars Tom Skerritt, Sigourney Weaver, Veronica Cartwright, Harry Dean Stanton, John Hurt, Ian Holm, and Yaphet Kotto.

Ripley (played by Sigourney Weaver) is introduced as a warrant officer aboard the Nostromo, a spaceship en route to Earth from Thedus. Having been placed in stasis for the long journey home, the crew is awakened when the Nostromo receives a transmission of unknown origin from a nearby planetoid. Following their landing, an unknown creature infiltrates the ship and kills every other member of the crew. Ripley is the only member to escape from the Nostromo, prior to her planned explosion of the ship, instigated to kill the monster. However, she discovers that the Alien is also aboard the ship's shuttle, but expels it into space before putting herself in stasis for the return trip to Earth.

'Alien' was released on September 6 in the United Kingdom. It was met with critical acclaim and box-office success, winning the Academy Award for Best Visual Effects. It has been consistently praised in the years since its release and is considered one of the greatest films of all time.

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