Taiwanese female writer Xu Ruoqing (Ruby Lin) moved to the mainland to live with her lover Zhao Yitang (Francis Ng). Before leaving, her mother (Elaine Jin) gave her the key to the old house left by her ancestors, so Ruoqing and her daughter Xiaomeng (Zhang Yuwen) moved into the legendary haunted house - No. 81 Chaonei. Yitang's wife (Xia Wenxi) refused to divorce, and he often worked with his secretary Liuli (Mo Xiaoqi), which made Ruoqing uneasy. There was no one in the huge house except an old servant (Yuan Xiangren), but Xiaomeng said that she often played with a little sister in red. The bold Ruoqing wanted to find out, but accidentally discovered the dusty past of the house. It turns out that all this is closely related to the original owners of the old house, the three brothers of the Huo family. The third young master of the Huo family, Huo Lianqi (played by Yang Youning), wanted to marry the top prostitute Lu Dieyu, but Lu Dieyu had a ghost marriage with the second young master (played by Li Jing) by mistake. This farce directly led to the overall decline of the Huo family in the future... In reality, Ruoqing increasingly felt the supernatural power of the house. This film is adapted from the weird story of "Chaonei No. 81", the first of the four haunted houses in folk legends.