The film tells the story of Sun Wukong, who, trapped in the "civil and martial fires" of Taishang Laojun's alchemical furnace, gives rise to an inner demon. To suppress his own malevolent thoughts, Sun Wukong uses the Golden Hoop as the core of a sealing array to imprison it. However, the inner demon unexpectedly breaks free from the seal, triggering a fierce battle between him and his own inner darkness.