"This dissertation studies the French novel of the interwar period from a particular pattern, that of the adolescent in the urban crowd. It constitutes a center point around which circulate debates and contradictions of this historic moment, for example between the hope of a better future and the memory of the war, between subjectivity and anonymity, between daily uses of the city and architectural projects. Through microlectures of Les Beaux Quartiers by Louis Aragon (1936), La Conspiration by Paul Nizan (1938) and Le Sursis by Jean-Paul Sartre (1945), it shows how the encounter of the adolescence and the crowd in important scenes in each of the works considered helps uncover tensions in the "social semiosis" and, specifically, in the urban imaginary of the years 1919-1945. It convenes in support of the demonstration many fictions that come into intertextual relationship with the three main novels of the corpus. All these literary works are read in interaction with a discursive corpus, which comprises a large amount of medical, political, religious and urbanistic texts. We postulate that the teenager in the urban crowd acquires in the novels of the interwar period an allegorical dimension that makes him what we have called a "novelistic chronotype". This hermeneutic concept, developed from the critical work of Mikhail Bakhtin, Walter Benjamin and Pierre Sansot, takes a form that highlights the sociality and the historicity of the selected corpus. Both of these aspects fall within the five modes of "semiotisation" that drive the "social imaginary" (Pierre Popovic): the narrativity, the theatricality, the poeticity the cogniticity and the iconicity. Studying the novelistic chronotype that we have identified is essentially to put the emphasis on its critical function, which affects the very form of the literary work. Each of the three chapters on the three selected novels first analyses the way they treat the language and represent time and space. It then develops a "microlecture" of a specific scene where a teenage character is immersed in the Parisian crowd" --