The story is about the young cop named Wei Shen. He then spent his childhood in San Francisco with her mother and sister come to Hong Kong. But in Hong Kong Chinese mother and sister are murdered by gangs. Wei Shen beginning of the game you're dealing with a drug gang are seen. In ambush murder of his police colleagues who suddenly comes and goes together. Police arrived and arrested everyone has been doing. After Wei's story is released from custody by the police and its mission to infiltrate back into the team continues Sun On Yee. He will need every bit of it to destroy the core activities of a criminal gang during an undercover police officer as well.