As the Tang monk and his disciples, including the reformed Wukong, Bajie, and Wujing, continue their pilgrimage, they encounter an unexpected environmental challenge. Despite it not being summer, the air grows unbearably oppressive. Upon seeking refuge in a local village, they learn from an old man that they are in the shadow of the "Mountain of Flames." The man explains that the mountain is "always burning" and that the surrounding land is similarly consumed, making it "impossible to pass" or even bypass, as the flames stretch far to both the north and the south.
The villagers reveal that these are no ordinary fires; they are "magical." The only solution lies with a powerful figure known as the "Iron Immortal," who possesses a "special fan" crafted from a "plantain leaf" capable of extinguishing the supernatural blaze. Driven by his characteristic confidence, Wukong declares, "I am as powerful as a god," and immediately departs to confront the Iron Immortal, ignoring the old man’s warnings that she "won't listen" to him.
Upon arriving at the Iron Immortal’s cave, Wukong’s attempt to "borrow" the fan is met with immediate hostility. The Iron Immortal identifies Wukong as her "worst enemy." The source of her rage is deeply personal: she is the wife of the "Bull Demon King" and the mother of "Red Boy." She blames Wukong for the fact that her son is now a "prisoner of the Bodhisattva Guan Yin."
Though Wukong attempts to clarify that Red Boy is now a "student" of Guan Yin and "isn't evil anymore," the Iron Immortal finds this transformation even more unacceptable. Her refusal to cooperate is absolute, fueled by her desire to protect her family's honor and her resentment toward the monkey's past actions.
The encounter concludes in a display of raw magical power. When Wukong persists in his demand to "borrow your fan," the Iron Immortal takes action. With a single wave of the plantain leaf, she generates a "furious wind" that physically removes Wukong from the scene. This decisive act highlights the significant threat the Iron Immortal poses to the pilgrims' quest, leaving Wukong to grapple with a formidable adversary who holds the literal power to extinguish their path forward.