Young Alvise, the only heir of a wealthy industrialist thinks he is paralyzed. He receives treatment for his psychological problem. His father sends him for a few days in the care of Lea, his wife's sister. She is a beautiful psychiatrist and tries to heal her psychopathic, impotent nephew. He becomes infatuated with her and she also reciprocates gradually. She breaks off her relationship with Stefano to be with her nephew. Alvise promises to make love to Lea if she plays with him and beats him at any of the games. She is intelligent, youthful, full of style and charm, becomes a toy in the hands of the boy and indulges in the murky game. They play a number of games.