Stalker is a 1979 Soviet science fiction film directed by Andrei Tarkovsky with a screenplay written by Arkady and Boris Strugatsky, loosely based on their 1972 novel Roadside Picnic. The film tells the story of an expedition led by a figure known as the "Stalker", who guides his two clients—a melancholic writer and a professor —through a hazardous wasteland to a mysterious restricted site known simply as the "Zone", where there supposedly exists a room which grants a person's innermost desires. The film combines elements of science fiction and fantasy with dramatic, philosophical, and psychological themes.