Among the Gouro masks, Zamble, a composite animal figure, and Gù, a fine-featured woman's face, are known to art lovers around the world. Today their profane avatars, Flali and Zaouli, are at the heart of masquerades that are much enjoyed by audiences. But this appreciation concerns only the ‘pretty’ aspects, that is to say the civilized and orderly side of an ensemble that also has a reverse side: the disease masks, sprung from disorder, avatars of the more powerful Zàùlì, described as the wild brother or husband of Zamble in the genealogical idiom employed by the Gouro when referring to the masks. These masks are created by each generation of young people and are central figures in rituals of inversion that express the upheavals of the times. At the same time as they establish their creators’ reputations, they serve as a record of these events for the Gouro. Descended from the initial trio of masks (Zàùlì, Zamble, Gù), they prolong the trend to secularization of this family of masks from the sacred wood. In tracking this tradition over twenty years we can see a process of resacralization. When the youths’ comments are analysed in the light of encyclopaedic knowledge acquired in the course of anthropological research on health, we can understand the necessity of the mask figure, and going further can understand what an ugly profane mask is, what it presents and the role it plays. In return the Zamble mask and its associates take on another dimension, a dimension that opens up exploration of the unknown via their intrinsic ambiguity and the transgressive behaviour they allow during the time of the ritual.