The five ghosts in Infernal Affairs are: Liu Jianming, Lin Guoping, Yang Jinrong, Shen Zao and Jun Chen.

1 year, Liu Jianming secretly entered the police and became a senior inspector of the Criminal Intelligence Bureau. Liu worked diligently in the police force for many years, and with his secret support, he provided a lot of information about enemy triad crimes, which made him step by step in the police force and promoted to chief inspector every year.

2, Lin Guoping undercover into the police internal criminal intelligence bureau, is a subordinate of Liu Jianming, he admired Liu Jianming very much, after Liu Jianming was transferred to the major crimes unit, he often helped him to do external work. It was not until Hanchen's death that he let Liu Jianming know that he was also a police undercover.

On the 3rd, Yang Jinrong went undercover into the underworld, and the police sent him to reveal the news of the police, so as to gain the trust of Chen Han, while Shen Orange, a mainland policeman, was sent to pretend to be an arms dealer and cooperate with Han Shen!

The mainland police in Shen Zao, like Yang Jinrong, are undercover in the underworld.

Jun Chen was an undercover. He entered the police station and was finally caught by Yang Jinrong, so he shot himself.