With the aim of encouraging a critical rereading of Mirbeau’s most durable works, this study examines his problematic status as a producer of fictions, his use of humour and cruelty, and his treatment of social class and biological diversity, making detailed reference to four books written in the second half of his career: Le Jardin des supplices, Le Journal d’une femme de chambre, Les 21 Jours d’un neurasthénique and La 628-E8