Miron and Melita, a brother and a sister, go to visit their friend Zoltan (Liptus) in Kopacevo for winter vacation. The local residents and hunting lodge members there are involved in a big campaign to help the wild animals from the reserve to survive the winter. The same night Miron and Melita arrive, a boy named Halasz is found half-frozen at the edge of the swamp where, he raves, he was attacked by a white ghost on one of the islands of the swamp. From then on, he can no longer talk. The old woman Etelka reveals the secret that the ghost had been first seen long ago and that you cannot go to the island because the ghost wreaks vengeance on anyone stepping onto the island. Fear takes hold in the place. The hunters, with Vucevic, Kovacevic and Levay taking the lead, begin an investigation. However, neither they nor the doctors can help Halasz. Therefore Miron, Liptus and Melita decide to find the ghost and offer to carry it off the island to the shore in exchange for making their friend well again, but the ghost shoots and wounds the hunter Levay, proving that he is much more dangerous than was previously thought.