The heroes of this novel will have pre-graduation practice on a geological expedition. They see the trip as a fun, interesting adventure. But a tragedy occurs - the helicopter transporting them to their destination crashes. The guys manage to escape and find themselves in the remote taiga. But they soon discover that something mysterious and terrible lives next to them. An unknown force is killing the boys one by one. Only one young man manages to survive. Remembering what happened, he tries to answer the question of what killed his comrades. The solution turns out to be shocking.