Wong Ying Gu (Nancy Sit Ka Yin) is a happy-go-lucky, helpful person who lives for the day with her family and granddaughter, Suen Man Wah (Irene Wong Lam). She is great friends with her neighbor, Wong Chi Cheung (Hui Siu Hung) and his son Wong Kim (Lawrence Ng Kai Wai) sees her as his own mother. HK in the 1950's is rife with corruption and in order to pay off her gambling debts, Ying often takes takes the blame for petty crimes and serves time in prison in place of the criminals.

On one such occasion, Ying agrees to the job without even asking the crime and is tricked to take the place of a murderer, she is sentenced to death. Just before the execution, Ying cuts off her braided hair and instructs the prison warden to give it to Wah as a keepsake. After Ying dies, her spirit lives on in the braid, but it is kept in the evidence room in the police station and she can't get out because of the Kwan Kung god figure and so it stays there for 10 years....

Very soon, Kim is grown up and has become a police officer. He is upright and honest and does not succumb to the culture of corruption. As a result he is sent to look after the evidence room, where he finds the braid and meets Ying again. Yip Ka Sing (Eddie Cheung Siu Fai) was the man who framed Ying all those years ago and is now the superintendent. He moves the Kwan Kung god and releases Ying's spirit from the braid. Ying misses Wah, so Kim agrees to help Ying find Wah and with Ying's help, Kim gets good results on many of his cases. Eventually, Ying finds Wah's whereabouts but is dismayed to find her being framed for another crime.....