On their wedding anniversary, Xu Ming's wife, An Ya, returns home late. That night, Xu Ming notices the word "Qiang" written on her waist. Although An Ya explains that it's a mark from a game she played with a female colleague, Xu Ming becomes suspicious when he learns that her company's manager is named Zhao Qiang. Seizing the opportunity while An Ya and the manager are on a business trip, Xu Ming decides to follow them and investigate.
