A young scientist, Kirill Voitkovsky, arrives at the scientific camp on Lake Yantar. At this time, in the Zone, a large-scale special operation is under way, involving a great deal of equipment. For unclear reasons, Kirill has partially lost his memory. Trying to restore it and find a way out beyond the Perimeter of the Zone, he realizes that he is the key to an important experiment—and now someone is hunting him…