Genius expert technological criminal Yiu Shing Tin (Wong He) loves to challenge justice and believes that his actions only become a crime when he is arrested by the police. However, his genius is not perfect and Tin has a weak point - emotion. Unable to handle his emotional affairs, Tin meets his half-sister Kong Kin Yee (Myolie Wu) with whom he shares a father and he doesn't know where to turn.

Commercial crime investigator Chong Chin Pang (Eddie Kwan) sends police cadet Tong Ka Ming (Jack Wu) to infiltrate Tin's software house as an undercover agent. How would Tin be fooled? He wants to play a game, to change Ming into someone just like himself!

Also wanting to change someone is Yee. She finds out about Tin's computer crimes and she wants to change his bad ways into good. At this time, she finds out that her beloved Ming is a cop and questions the sincerity of the love between them.

Everybody has his/her own values and beliefs. Sometimes it can be hard to distinguish between the good and the bad. So who influences who?