| Director | David Lam |
|---|---|
| Budget | $10 million |
| Box office | $118 million |
Natalie Liu reports second generation rich heir Cho Yuen-yuen to the Independent Commission Against Corruption (Hong Kong) (ICAC) for bribing prison officers for parole. William Luk goes undercover as a prisoner to investigate the case, while being aided by his colleague Kenny Ching, and friend, Joint Financial Intelligence Unit (JFIU) officer Lau Po-keung the outside of prison.
In prison, Luk encounters old rival, Wong Man-ban, whom he imprisoned five years ago. Wong has become a major gang leader within the prison and is bent on seeking revenge on Luk. Prison superintendent Shum Kwok-keung, who accepts bribes from Cho, turns a blind eye on prison scuffles. Fortunately, Luk was able to find assistance from fellow inmate Wong Lam-luk, a well-meaning young man who seeks refuge in prison to avoid high living expenses.