Polyphonic narration is a central critical concept that highlights the multiplicity of independent and interacting voices within a literary text, where these voices intertwine to reflect the diversity of human consciousness and experiences. This enriches the text and gives it a complex depth that transcends narrative monism, allowing for multi-dimensional readings. Mikhail Bakhtin's theory provides a fundamental framework for understanding the literary text as a dialogic space in which multiple voices and discourses interact, where no single voice dominates, but rather diverse and conflicting voices intersect to reflect the social and cultural plurality, granting the text a dynamic depth. This research aims to analyze the most prominent manifestations of polyphony in Fadil al-Azzawi's novel "The Fifth Castle", according to Bakhtin's theory, employing the descriptive-analytical method to examine hybridisation, expressive genres, and pure dialogues. The findings reveal that the novel clearly embodies polyphonic features, as the multiple voices of the characters interact through hybridisation between the language of official authority and popular satirical dialects, and between seriousness and sarcasm, reflecting the conflicts between the authorities and the detainees. The interweaving of expressive genres also emerges in the fusion of political discourse, philosophical reflection, and realistic and analytical narration. Pure dialogues and the narrator's internal monologue work to expose the intellectual, psychological, and ideological struggles among characters by presenting individual stances vividly, reflecting Bakhtin's dialogism and transforming the novel into a dynamic space rich in meaning.