The authors present two vignettes from a group-psychodrama they conduct within a psycho-analytic therapeutic institution. This to illustrate the way the group evolved from an “anhistoric” state to a fraternal group, through the imagos summoned through the sessions. In this paper, the authors also put into perspective the changes within the group as they appear in the external reality, in particular the departure of some participants, and the internal dynamics related to the activation of imagos within the group. Unbeknownst to the participants, successively arised the imago of the archaic father, functionning as a totem, followed by the imago of the almighty mother. It is gradually, once these imago will have been given space, identified, interpreted and transformed by the group that the fraternal group will emerge. As in ontogenesis and phylogenesis, the group, in its processual construction may evolve from being driven by imagos to functionning through identifications, from the archaïc father to the fraternal group.