Directed by Ridley Scott and released in 1979, Alien follows a crew of seven who find themselves on a foreign planet upon intercepting a distress signal while travelling back to Earth. With a damaged spacecraft they find an environment that seems off and upon one of their own getting injured they venture back inside their spacecraft. However, they soon learn that it is not what they left behind that is dangerous, but instead, what they let in. Filled with suspense and tension Alien is a horror classic that is a must-see.