Justice in the Dark Episode 17

Luo Wei Zhao learns from Tao Ze that the wife of his former teacher, Yang Zhao Feng, is seriously ill and has only a short time left to live. Yang Zhao Feng's wife entrusts Wei Zhao with a letter left behind by Yang Zhao Feng. In the letter, she expresses her concerns and regrets about a certain incident. Meanwhile, the Special Investigation Department receives news of an incident. Five boys and girls attending a boarding school have run away from school and disappeared. It seems that there is no criminal element to it, but the gruesomely murdered body of one of the five male students is discovered. (Source: Japanese = wod.wowow.co.jp || Translation = MyDramaList)