The Devotion of Suspect (played by Zhang Luyi) met middle school teacher Shi Hong (played by Zhang Luyi) when they were young, and they sympathized with each other because of their common interest in mathematics. Many years later, when Tang Chuan was investigating a murder case, Chen Jing (Ruby Lin), who was Shi Hong's neighbor, As a result, Shi Hong and Tang Chuan reunited again, but Tang Chuan discovered a bigger secret during the investigation... Forced to stand on opposite sides, Tang Chuan and Shi Hong launched a high-IQ duel, which gradually pushed the story towards a shocking and frustrating ending.