AbstractThis study examines the problem of evil in Iranian mythology, focusing in particular on water-related myths and drawing on Georges Bataille’s philosophical theory of the sacred and the profane. Bataille considers evil not merely as the absence or negation of good but as an active, tragic, and creative force intrinsically connected to the sacred and to the deepest dimensions of human existence. Based on this interpretive approach, the concept of evil in Iranian myths is analyzed beyond simple moral dichotomies of good and bad and is instead understood as a fundamental and necessary force operating within the very structure of existence, nature, and the cosmos. The myth of Tishter exemplifies this perspective, where the sacrifices offered to Ahura Mazda are not only life-giving forces but also ethical, spiritual, and sacred actions aimed at restoring and maintaining cosmic order, harmony, and justice. The battle between Tishter and Apaosha, contrary to purely natural, meteorological, or dualistic interpretations, encompasses ethical, metaphysical, and symbolic dimensions, and it reflects the active and inevitable presence of evil within the continuous flow of life, creation, and cosmic balance. A similar structural and thematic pattern is observed in the Indian tradition in the myth of Indra and Vritra, where acts of divine sacrifice and killing paradoxically result in the restoration of cosmic balance, moral order, and spiritual renewal. These concepts are also mirrored, reinterpreted, and dramatized in two modern Iranian plays: Nagahan by Abbas Nalbandian and Broken-Winged Angel by Ebrahim Maki. In Nagahan, life-giving elements paradoxically transform into destructive forces, and the sacrifice of Fereydun is interpreted as both a tragic, existential, and ontological necessity. In Broken-Winged Angel, the notion of sacrifice is linked to the process of awareness, self-realization, and liberation from human limitations, resembling the philosophical experience of escaping Plato’s cave. Despite formal and stylistic differences, both works emphasize that evil and sacrifice are fundamental components for understanding the sacred, achieving awareness, and reconstructing the cosmic order.