Revision with unchanged content. This study analyzes four of Javier Mar as's novels, Todas las almas, Ma ana en la batalla piensa en m , Negra espalda del tiempo and Fiebre y lanza, as well as selected journalistic articles. It focuses on their antirealist elements, such as the melding of seriousness and humor, the incongruous mixture of history and fiction, and the unreliability of the intrusive narrator. It places Mar as in the context of the post-Franco years and chronicles his rejection of the literature of social realism and his incorporation of postmodern tendencies. It also examines different types of humor in his novels through the application of Bakhtin's theory of the carnivalesque, Victor Shlovosky's theory of estrangement, Geoffrey Harpham's studies on the grotesque, and Mar as's own manipulation of history. This study also analyzes the juxtaposition of fact and fiction in Negra espalda del tiempo, challenges readers to make sense of the text, and raises questions about authorial reliability and textual stability. It shows how Mar as incorporates humoristic techniques and fictive devices in his essays to make readers aware of cultural and political change in Spain. This book should have significant relevance to readers interested in Javier Mar as and contemporary trends in Spanish literature.