Social skills training (SST) has recently emerged as a typical application for emotional conversational agents (ECA). While a number of prototypes have targeted the general population, fewer have been used for psychiatric patients despite the widely recognised potential of ECAs technologies in the field of mental health. Social cognition impairment is however a widely shared symptom in psychiatric patients suffering from pathologies such as schizophrenia. Going further than SST, rehabilitation programmes involving role-play, but also problem solving have been successfully used by clinicians, drastically improving the quality of life of patients suffering from such disabilities. One of the challenges of these programmes is to ensure that the patients will be able to adapt their behavior when the situation varies, rather than training them with the appropriate behavior for a set of specific situations. In this paper, we describe a novel approach for the development of a serious game supporting rehabilitation programmes for social skills, which will primarily target schizophrenia patients. We propose to use an ECA in combination with a narrative generation engine issued from interactive storytelling research to provide varied situations. This approach reflects the combination of both role-play and problem solving exercises on which remediation therapies rely, and has the potential to support patient's progress and motivation through the rehabilitation programme.