In a decaying and solitary mansion, Edward and Alice, the threshold of the twenty-fifth year of marriage, they await the arrival of Francois, a young and well known psychiatrist, called to make a diagnosis about Viola, their twenty-five year daughter, who lives bordering on anorexia. The presence of the psychiatrist gradually unleashes a family war for the conquest of the "prey": Francois himself. And Viola, beginning the weakest, will do everything to turn in her favor a state of subjection, which had been unbearable.