Four sisters reluctantly return home to the country to visit their ailing, embittered father over Christmas. Their father believes that his current wife has tried to poison him but Dr. Lindsay, the local physician, and the sisters disagree. Then a storm causes the roads to be flooded and the telephone lines to not work. Soon it becomes clear that someone wants to kill the family, as well, when one of them is found murdered. One sister then tries to run through the woods to reach Sheriff Nolan for help. But she has her own encounter, as she sees someone chasing her while dressed in a large poncho carrying the pitchfork. She returns home, only to discover more murders. The prime suspect becomes father's wife, but was it someone else?