Stalker is a 1979 Soviet science fiction art film directed by Andrei Tarkovsky with a screenplay written by Arkady and Boris Strugatsky
The film tells the story of an expedition led by a figure known as the “Stalker” (Alexander Kaidanovsky), who guides his two clients—a melancholic writer (Anatoly Solonitsyn) seeking inspiration, and a professor (Nikolai Grinko) seeking scientific discovery—through a hazardous wasteland.
This is based on the novel Roadside Picnic, by the same writers, which is also the source of the S.T.A.L.K.E.R. video games.
It was also a major influence on Annihilation.
Roadside Picnic is fantastic.