Lucie and Lucien, in their mid-twenties, have lived together for several years. After having failed his exams to become a policeman, Lucien gets hired as a secret agent. His cover will be that of a dilettante, a happy-go-lucky fellow, and he mustn't tell anyone about his real work, not even his closest friends or relatives. This masquerade that he is forced to play allows him to meet Jennifer, a young woman who takes Lucien to be a great seducer and therefore just the man who can take charge of her sexual initiation. Lucie, meanwhile, is troubled not only by Lucien's sudden capriciousness but also by a recurring dream that awakens her every night and which upsets their relationship. After Lucie goes to see a psychologist she is convinced that in order to make her relationship with Lucien more truthful and profound they will have to tell each other everything. But Lucien's professional secret and the initiation business with Jennifer make this impossible...