In the 1950s, Edith Hardy, a beautiful woman in her forties, runs her own private detective agency in the 12th district of Paris, investigating within the circles of perfumers and scientists, and dealing with inheritance matters and the like. Like Léo Malet in his novels, Pierre Christin and Annie Goetzinger have chosen this environment and time period as the backdrop for their story. The reader moves through the lives and urban landscape of a perfectly depicted capital: whether it's clothing (a concierge without a headscarf holding her broom; office workers in hats or laborers in work coats; young women in sheer negligees or knee-length suits), cars (the first Citroën DS appearing as competition to the Ford Vedette), or landmarks (including the famous lions at Place Félix-Eboué).