This book is the study of the extraordinary destiny, in the history of European culture, of an object which could, at first glance, seem quite ordinary. It tells the story of a mask, the cast of a young girl's face entitled 'L'Inconnue de la Seine, ' the Unknown Woman of the Seine, and its subsequent metamorphoses as a cultural figure. 'L'Inconnue' names the death mask of a girl who supposedly drowned herself in Paris at the end of the nineteenth century. Legend has it that the forensic scientist tending to the corpse awaiting identification on a block of ice at the Paris Morgue, was so struck by her allure that he captured in plaster the contours of her face. The unknown girl, also called "The Mona Lisa of Suicide", has become the object of an obsessive interest that started in the late 1890s, reached its peak in the 1930s and continues to reverberate today.