Juste la fin du monde [It’s Just the End of the World] by Jean-Luc Lagarce (1990) is a play that depicts a family gathering on a Sunday to mark the return of the eldest son, who, having been distant from his family for a long time, has comes back with the intention of announcing his imminent death to his relatives. For a reader or spectator familiar with the author’s biography, the text of the play contains numerous similarities to Lagarce’s life, and the main character, Louis, bears many resemblances to Lagarce. However, one cannot categorize this play as autobiographical because the author does not claim such an approach and has he emphasized some clearly fictional elements. Nevertheless, through the play’s narrative and scenic techniques, it evidently offers elements of self-writing. Thus, this study attempts to address the following questions: What is the nature of the elements of self-writing in this play? How can they be categorized? Can autofiction be mentioned? What are the stakes involved? To answer these questions, this article initially focuses on the play itself, its author, its writing context, and its basis while considering the novelty and specificity of the theatrical forms highlighted by Lagarce. Subsequently, the article explores the self-writing revealed in the play, first by attempting to define the genre and its subgenres (i.e., autobiography, autofiction, autonarration, and autofabulation) and then by determining which elements in the text related to this writing belong to which categories. Lastly, the article seeks to understand the stakes and functions that underlie the use of these specific techniques. Juste la fin du monde is a complex work with multiple dimensions and readings that are challenging to summarize while conveying the substance of the text. This play is one of Lagarce’s most well-known, especially due to its recent adaptation to film by Xavier Dolan, and can perplex readers and spectators with its innovative use of theatrical structures and the distinctive style of its dialogues. If reading is a moment of laborious pleasure, watching the play adds to this pleasure and the dimensions of the work, especially because the director has contributed to constructing meaning by filling the gaps the author left regarding the direction of the play on stage. Juste la fin du monde creates a sense of blurred lines between fiction and reality: One hesitates between the presence and absence of the author in the work, and determining to which type of self-writing it belongs has been challenging. This analysis of the elements of self-writing based on a definition of its various categories has led to identifying the play as being on the border between autofiction and autonarration because it stages a dramatization of an episode from the narrator’s life: the attempt to return and express imminent death. However, the play also employs the three processes Gasparini (2009) mentioned for defining autonarration: fragmentation, metadiscourse, and alterity (Gasparini, 2009). Fragmentation occurs because, similar to the formal structure of the play, the elements of self that are scattered throughout the work are disparate and only enunciated through fragments and pieces of memories evoked by different characters, sometimes contradicting each other. This gives rise to otherness due to the presence of different perspectives proposed for the same facts over which the quasi-spectral presence of the author’s heteronym, Louis, introduces a metadiscursive discourse that never aims to explain or unravel the complex situation represented in the play. This study has thus determined the possibility of self-writing here to have served a retrospective function, a reconstruction of the author’s self as an attempt to articulate the unspeakable aspects of his existence. The works of Lagarce, both through his diaries and the staging of his heteronyms and doubles, has constantly employed various techniques of self-writing as tools for the quest of the past, the quest for understanding and self-expression in the most tragic aspects of existence.