Fanny Legoff, a renowned and admired biologist, has lived in Paris for over fifteen years, having left the Brocéliande campus during her studies following the disappearance of her best friend, Laura, for which she had been suspected. When Fanny receives a package containing a sickle covered in dried blood and a letter again accusing her of being responsible for Laura's disappearance, she decides to return to her native region, fifteen years after the tragedy.