Long-time fans of the game series probably already know this, but bleak open-world shooter STALKER isn't an entirely original concept, as it's based loosely on the premise of a 1979 art film called Stalker.
There's not too much in common other than the name, but in a great piece on the New York Review of Books, Gabriel Winslow-Yost sits down and really compares the two, finding that while the game may take more than a few liberties with the source material, both are at heart still dealing with very much the same thing.
And that in an even more interesting way, the STALKER game isn't so much an adaptation of Andrei Tarkovsky's film, but of the book which in turn loosely inspired it, Roadside Picnic.
In some ways, the video games are closer to Tarkovsky's source material than to Tarkovsky. In the Strugatsky brothers' Roadside Picnic, the science fiction book on which the movie is loosely based, the stalkers are numerous and mercenary. The elements of the Zone are many, and named, if not quite explained-there's "Mosquito Mange" and "Burning Fluff," "Full Empties" and "Black Sprays." In the film most of these are not present-Tarkovsky leaves in only one, the "meatgrinder," though his Stalker is clearly terrified of many more. But the video game returns them, and adds more: strange traps known as "anomalies," that crush, dismember, and electrocute; and "artifacts," weird little objects with supernatural properties-infinite batteries, death rays, and so on-which are the reason people venture into the Zone. (In Roadside Picnic both the anomalies and the "artifacts" are discarded alien technology; in the games they are somehow the result of the nuclear meltdown.)
Fans of the games, which were recently announced to be getting a spiritual successor of sorts, should definitely give it a read.