Despite the fact that he comes from a long line of disciplined workers, LAW YIU-WAH (Moses Chan) is a teacher of a notorious school. One day, he is urged to resign after being vilified by his students as a peeping Tom. The triad has expanded their drug network at local schools. WAH, who has turned a cop, is told to go undercover at the school where he used to teach. He is impressed by the enthusiasm of a new teacher HO MIU-SUET (Tavia Yeung). He also comes to realize he was too strict with his students in the past.