Brother Laughing (Michael Tse) is a member of the triads and works for the big boss, No. 1 (Anthony Wong). Due to a strong bond, No. 1 arranges for Laughing to join the Police to become his mole. Laughing graduated top of his class and because of his bad boy image attracted the attention of the Head of District Anti-Triad Squad who arranges his assignment as an undercover cop to infiltrate the mob. Laughing is now a double mole. How will Laughing contend with the law and the triad brotherhood?