1. 'Alien' (1979)
Here is Scott's other genre-defining work. It's "Ten Little Indians" in space plot gives license to a very grounded, and terrifying, monster hunt centered on blue-collared workers confronted with an evil that literally makes chests explode.
"Alien" turned Sigourney Weaver into a star, and her character, Ripley, into an icon -- all while paving the way for more smart, female-driven genre fare. So many films, to varying degrees, owe their existence to this one, which is responsible for teaching us that, in space, no one can hear you scream.