Denis, a hypersensitive teenager, is revolted both against his distant, pretentious, well-to-do parents and their superficial society firends and the stiff, intolerant catholic establishment in which he studies. Fortunately,he has an open-minded philosophy teacher, Father Philippe de Maubrun, who understands him and supports him in his distress.

In a small provincial town, students meet at a party organized by one of them, and share their thoughts on the difficult year they are leaving : the preparation of high school diploma.