January1959, SovietUnion.IntheicyUralMountains, agroupofninestudentssetsoutonaskitrek.Eventhoughtheyallarewell-experiencedhikers, theyneverreachtheirdestination.Astheirbodiesturnupamonthlater, itleaveslocalinvestigatorspuzzled.Theirtentwascutopenfromtheinside, theyarefoundfrozenstiffintheirunderwear...