On August 1933, an 18-year-old girl named Violette Nozière poisoned her father. Once arrested, she justified her act by declaring she had wanted to take revenge on her father for his incestuous behaviour towards her. This article studies one of the most famous cases of the interwar period with respect to the issue of incest. In which way did society deal with the possibility of a young woman being raped by her father ? Even though this possibility remained for a large part an unspeakable taboo and was rejected at the end of the investigation, the incest accusation explains why the case aroused wide interest : incest became visible and was publicly debated. This study argues for a microhistorical approach to situate the early decades of the XX^th century within the history of sensibilities to sexual violence.