Senior Lieutenant Alexey Kartash comes to serve in a Siberian prison camp located near a remote taiga village: he was transferred from Moscow for a love affair with the General's daughter. By chance, a young officer discovers that far from the zone in the forest is a mystical place — Simankina pigweed. Once there, people disappear without a trace. Local residents tirelessly compose legends about mysterious swamps. Kartash decides to open the veil of the mystery of this disastrous place. He learns that there is a camp in the swamp where people are working in a secret mine under the supervision of armed guards. Alexey understands that he is involved in a dangerous game, and there is no way back.