Wang Wanqing, the orphaned daughter of the Wang clan of Taiyuan, married into the Wang clan of Langya three years ago. She has endured her husband Wang Xun's coldness and the bullying of Xie Wan'er, his second wife. Her entire clan is falsely accused of collaborating with the enemy and sentenced to execution. Finally, Xie Wan'er personally forces her to drink poison and abandons her in a mass grave. At the brink of death, Bai Jiuniang, a thousand-year-old fox demon, offers her a bargain: exchange her soul for the fox demon's body and powers. Reborn in a new skin, the woman who was once Wang Wanqing undergoes a drastic transformation. Unleashing her full demonic power, she uses Wang Xun to kill Xie Yan. Xie Wan'er has Wang Wanqing dragged to the execution ground, where she transforms into a gigantic nine-tailed fox before the eyes of the crowd and begins her final judgment of her enemies.