Just before taking an irrevocable and tragic step, Caroline talks to Claire, her lycée friend. Later, Claire gathers five other school friends, and tells them Carolines secret. The six agree to wage a guerrilla war against their philosophy teacher, the sarcastic and belittling M. Terrien, the cause of Carolines despair. After seeking advice from Mayard, the schools guidance counselor and a leftist with a police record, the six look for evidence that could get Terrien fired. They strike gold, and then raise the stakes. Sarah, one of the six, hatches a deadly plan.