At the wedding of a tycoon in Shanghai, the bride is kidnapped. Inspector Zhong Lang discovered that the kidnappers were the notorious "gravediggers". Gravediggers routinely lock their victims in an enclosed space with enough oxygen to breathe for 24 hours.

The French Concession Inspector Zhong Lang accidentally rescued Qian Shouchang, a wealthy businessman who was attacked by a killer. Boss Qian was very grateful and invited Zhong Lang to settle in the Qian Mansion on the day of his birthday banquet to ensure safety.

Taking advantage of the holiday, Yu Shengnan, a female professor at the Medical University, came to Guanghua Relief Society to see a doctor for the poor. Zhong Lang, the inspector of the patrol room, came here to visit Shengnan, and met Shengnan who had helped him back then.

Located in the Ma Sinan Road Prison in Shanghai's French Concession, the police detective Zhong Lang, his partner Han Fei, and Yu Shengnan, a female professor at the Medical University, jointly arrested Yu Liben, a murderer who cut his throat.

Prices are soaring, gangs, warlords, and foreigners are rampant and domineering. The oppressed and bullied people most hope that justice will come. So a group of righteous and brave young people stepped forward and used their wisdom and faith to disperse the darkness.

A rental house in Shanghai caught fire. Yu Shengnan, a female professor at the Medical University, found a woman's body very suspicious, so he quickly called the chief inspector Zhong and his partner Han Fei. After preliminary autopsy and on-site investigation, Katsuo and Zhong Lang concluded that the deceased was murdered before the fire...

Wilson, an important British official in the Shanghai Public Concession, was shot and killed in a bar.

In the old Shanghai before liberation, forces from all sides gathered here, and they grew up and down, rampant and domineering. The two major underworld forces, the Qinglong Gang and the Qilin Gang, often fight for supremacy, and blood splatters on the streets. One day, three members of the Qinglong Gang were dead on the street.

On a quiet day, Abin, a boxer who claims to be a friend of Zhong Lang, called the laboratory of St. John's University and asked Yu Shengnan to tell Zhong Lang that there was an important life-threatening matter to him.

The French Concession launched the "No Smoking Campaign", and a large number of opiums of the gang were seized. Han Fei accidentally got involved in a shootout in a restaurant.