The prequel to the popular character, Laughing Gor (Michael Tse) in the highly rated TVB drama series Emergency Unit. This movie tells the story of Laughing and before he join the police force has a dark background as member of a tried under Chou (Anthony Wong). Chou was the leader of the triad and persuaded Laughing to join the police force as an undercover for the triad to spy on police activities. While in the police academy, Laughing excel but not well enough to be confirm as a police officer. Instead he was recruited to be an undercover agent to spy on some illegal activities. Laughing now maintains the life as a double undercover agent, with crucial information from two sides. But an incident disturbs the balance of the two identities and threatens to blow his cover. With both the triad and police force suspicious of his loyalty, Laughing does not know who he can trust to save him.