One of the great founders of modern sci-fi.
Anyone who knows me already knows that I don't really like alien-themed movies, because I don't strictly believe in intelligent life outside our planet. However, the theme has already yielded many quality horror or thriller films. “Alien” is arguably the best, best-performed, and most enshrined and culturally significant of them all. It's one of those films that has already gone beyond cinematic issues to become a piece of art and culture that we all know, even people who never took the time to see it.
Thus, it is not worth wasting time explaining the plot around the “Nostromo”, a cargo ship with seven crew members who are decimated by a highly dangerous and carnivorous alien. The direction, in charge of Ridley Scott, is excellent, meticulous, attentive, and the story is intelligent, very well written and with well-developed and used characters. Contrary to what happens in other films, we see the characters trying to act as a team, and trying to solve an unexpected and dangerous situation. I never felt like they were acting in such a way as to almost purposefully put themselves in danger, which happens a lot in recent horror movies.
Sigourney Weaver made an excellent dramatic career after this film, which established her as an actress and opened doors for her in the industry. A deserved reward, given that she puts in her best efforts and gives this character all the resilience, humanity and charisma she deserves and needs. Despite the general quality of the cast being quite good, there are almost no actors capable of matching Weaver. As far as the technical aspects are concerned, the film has excellent cinematography (it even looks newer than it is) and really good special effects and visuals, considering that there is no CGI and that everything is done in the old-fashioned way. Finally, a word of praise for the iconic original score composed by Jerry Goldsmith.