The authors make reference in this work to a clinical case, which they have followed in cotherapy. The main passages of the sessions are described as well as the considerations which have come out from the work with a psychotic transactional family. The dynamics of the family are underlined in the study of the specific case to show how they are characterized by the mythic initial encounter of the couple, which has rigidly sealed their implicit pact. This is followed by the couple’s reciprocal attributions of mask roles, warning signs in the family’s vital cycle evolution of the triangulation of the children.
Keywords: Myth, mask role, psychotic transaction, triangulation