In dramatic literature, dialogue as the basis of the play includes the verbal interaction of the dramatic characters (either in the form of the conversations of the characters with each other, or a one-sided form i.e. monologue). An effective dialogue pursues at least one of the following goals: introducing the place, introducing the time, introducing the character, giving information or advancing the story. Aiming to find various and desirable solutions to write more creative and higher quality plays, in this research, with a descriptive-analytical method and using documentary-library sources and reputable internet sites, efforts are made to examine the dialogue in the L’envers du décor by Florian Zeller, on the basis on the concept of “distance” posed by Gerard Genet in his theory of narratology. It is hoped that we will be able to explain the effect of different types of expression (direct speech, free direct speech, indirect speech, free indirect speech) on dialogue writing and characterization. In this regard, by proposing the hypothesis that this play provides a suitable basis for the study of distance and different types of expression in Ge net’s theory of narratology, first the main framework of this research is briefly examined. Then the concept of distance and types of expression in the framework of Genet's narrative is expalined, and by showing how the types of expression are reflected in the play, the effect of types of expression in Genet's theory of narratology on dialogue writing and characterization will be expressed