A small port at the turn of last century, embedded in a romantic river landscape with dense woods and a large castle ruin on a hill. Laurin, a pretty girl aged nine, lives together with her young mother Flora, her father Arne and her somewhat peculiar grandmother, Olga, in a remote, ivy-clad cottage in the middle of the forest. Laurin's father is a sailor and he often has to leave his family back for more than a couple of months. One evening Flora takes her husband for the long way down to the harbour. On her way back through night and storm she dies under mysterious circumstances, crashing through the rotten railing of a long, wooden bridge and drowning in the icy water of the river. Flora's death appears like a horrible accident, yet her little daughter feels that something evil is concealed in the village community. Two years later, Laurin's father has gone off to sea again and the girl stays alone with her grandmother. It is now, that Van Rees, the parson's son, returns from the military service and is offered the job of the village teacher. Laurin feels somehow attracted to the dark-haired man with his gloomy and melancholy glance. With curiosity Laurin observes Van Rees' strange affection for her schoolfriend Stefan, remembering, that in the night of her mother's death a gypsy boy was attacked by a man in front of her window. From now on Laurin is tortured by bizarre dreams and visions. She realizes step by step that Flora and the gypsy boy have fallen victims to a murderer who haunts the castle ruin in the company of a black wolfish dog. Then Stefan suddenly disappears. Laurin scours the castle ruin and discovers a trapdoor leading down into a vault. There she encounters nightmare and terror.