For years, Conrad Lang has been getting by thanks to the rich Senn family. Initially a childhood friend of Thomas, then the caretaker of their holiday home in Biarritz, they use him as they see fit, and he's fine with that. But when his health deteriorates, and when he starts telling Simone, the young wife of the Senn heir, childhood memories that don't at all fit with the family's official history, Elvira, the matriarch, shows herself to be strangely threatened. It's as though this old, inoffensive fool carries within himself the means to destroy her. It is then that a strange friendship forms between Conrad and Simone, leading the young woman to stand up, for him, to an Elvira far more dangerous than it would seem.