The Tahmineh and Rostam episode, as presented in modern text-critical editions of Ferdowsi's Shahnameh, is compared vis-à-vis both the pre-modern scribal interventions in the manuscript tradition of the poem, as well as two oral presentations of the same episode by traditional storytellers (naqqālān), as preserved in their prompt-books (tumārs) and in recorded performances from the twentieth century. The mise-en-scène, the social circmstances, as well as the expansive nature of such oral performances, are described, and a translation of an oral version of the Rostam and Tahmineh episode is given. The narrative strategies employed to negotiate the intersection of new episodes or contemporary moralistic considerations with the written text of Ferdowsi's Shahnameh are then explored, analyzing the nature, motivations and functions of the scribal and oral interpolations to the Tahmineh episode, and demonstrating how modernizing reinterpretations impart a certain dynamism to the living Shāhnāmeh tradition. The naqqālān are shown to alter the Tahmineh episode to comply with the moral and religious values of their audiences, the requirements of extended narration cycles, and the horizon of expectation of the genre of epic. The article closes with a brief consideration of how moral and religious values apply differentially across various genres (heroic epic, romance, etc.), and how these differing horizons of expectation impact the reinterpretation of the narrative material.