Wei Yun, a criminal law professor at G University’s Law School, dies of high blood pressure. The day before she suffered the fatal attack, she attended a banquet held in her honor by her former students. Wei Yun’s family believes she was murdered, but proving that it was a murder requires conclusive evidence. As the investigation unfolds, various grudges between Wei Yun and her students come to light. The case also hinges on determining the causal relationship between the criminal act and its consequences.