Su Ruoshan set up a cruel trick and injured her leg while protecting Biyu in an attempt to make Yun Mu like her again.Yun Mu felt guilty, but expressed that she was only grateful to Su Ruoshan.Su Ruoshan was determined to get rid of Su Ruofei. She took advantage of Su Ruofei's guilt and first asked Su Ruofei to help her borrow lamp oil, and then asked Su Ruofei to the musical instrument workshop.There was a fire in the musical instrument shop, and Su Ruofei was arrested as a suspect of arson and taken to the supervision station.Yun Mu, Jin Shangyu and Huang Ying worked together to find evidence to clear Su Ruofei's innocence.