Why is Alien rated R?
Official MPAA Rating: Alien is rated R for sci-fi violence/gore and language.
This additional information about the movie’s content is taken from the notes of various Canadian Film Classification boards:Violence:
-Intense attacks by alien creature|gruesome and bloody violence
Infrequent use of the sexual expletive; profanity and scatological slang
|British Columbia||14A||Gory Scenes|
|Ontario||PG||Frightening Scenes, Language May Offend, Not Recommended for Young Children|
|Canadian Home Video|