It's Not Me, It's Him(1980)

Original title: C'est pas moi, c'est lui

Pierre Renard is the blackboy of the writer George Vallier. At the time of a reception, the Italian actor Aldo Barazutti takes him for the writer and proposes to him to come to work with him in Tunisia with the development of a scenario. In fact Barazutti wants only to flee her wife to find her mistress Valerie. Misunderstandings when Vallier joined them. They must flee in the desert a jealous husband...