S.T.A.L.K.E.R. is a video-game series inspired by the book "Roadside Picnic" (1972) by the brothers Arkady Strugatsky and Boris Strugatsky. It also takes inspiration the movie "Stalker" (1979) directed by Andrei Tarkovsky with a screenplay written by Arkady Strugatsky and Boris Strugatsky.

The game is set in the Chornobyl Exclusion Zone, a dangerous area walled off from the rest of Ukraine after a second catastrophe in Chornobyl made the area highly dangerous and anomalous.