Pierre and his wife Anne had a good thing going together, until their son Nicolas was born. Anne traveled with him on all his long truck journeys, and they had frequent and passionate sex. For quite a few years now, Anne has stayed at home to take care of their boy, who is a sickly, weedy little fellow. Pierre is frustrated. Anne is frustrated too but has her almost incestuous feeling for her son to torment her. Even little Nicolas is frustrated, in part due to the knowledge that his father feels that the sacrifice he and his mother made in raising him hasn't been worth the effort. He too has some release in the form of a good relationship with his gigantic dog. When the seething passions of these four discontented mammals reach a crisis point, the result (in this film) is exceedingly ironic.