Alien is a 1979 British-American science fiction–horror movie directed by Ridley Scott. It is called a science fiction movie because the story takes place in outer space, and there are alien creatures. The movie's title refers to a highly aggressive (angry) and intelligent extraterrestrial (alien creature) that attacks and kills the crew of the spaceship Nostromo. The movie stars Sigourney Weaver as Ellen Ripley, Tom Skerritt as Captain Dallas, and Ian Holm as Ash.
The extraterrestrials in the movies are usually called Xenomorphs.
Alien was a box office success (it made a lot of money). It led to a successful Hollywood franchise of books, video games, merchandise, and three official sequels (follow-ups). Along with launching the career of actress Sigourney Weaver, the movie is credited as being the first action movie to have a strong female heroine.
The famous tagline (slogan) for the movie was: In space no one can hear you scream.