This story was adopted from the life of Li San, the Swallow. During the early years of the Republic there was a well-known thief nicknamed "the Swallow" as he always left a swallow-shaped dart behind him. Chief detective Hou Baoshan asked inspector Li Debiao to visit veteran Jiang Shoushan for more information. Jiang was an admirer of "the Swallow" who always helped the poor with the treasures stolen from the rich. He felt somewhat embarrassed to receive Li but did not tell him anything about "the Swallow". Jiang was impressed by Li's smartness and wanted to marry his granddaughter Yinniu to him. Yinniu was very confident of her martial arts skills and looked down upon Li as a civil servant. She did not agree with her grandfather's suggestion. Li stated that "the Swallow" was excellent in his martial arts skills, leaving little track for investigation. Yinniu did not believe him and wanted to challenge "the Swallow". She took the swallow-shaped darts collected by Li and went to steal a bag of gold in a household, leaving a swallow-shaped dart behind.

It was widely believed that "the Swallow" had stolen again. Hou was under great pressure to arrest "the Swallow" by a deadline, which made him even more anxious. Li thought it was Yinniu who did it, and asked Jiang where the darts were. He said he had given them to his granddaughter. Yinniu said if "the Swallow" could steal the bag of gold from her, she would return the darts to Li. At night "the Swallow" did appear and steal the gold from Yinniu's room. Hidding himself in the dark Jiang noticed that "the Swallow" was actually Li. He was so excited that he asked a neighbour Dayu to propose to Li. On her way Dayu was harassed by Lu Laoyi, another inspector. Yinniu emerged and stopped him. Lu was attracted to Yinniu and asked Li to propose to Jiang on his behalf. When Li visited Jiang again, Yinniu expressed her love for him. Li was so happy that he pledged to marry Yinniu soon. Outrageous to receive the wedding invitation of Li and Yinniu, Lu accused Li of being "the Swallow" and put him in jail. Yinniu tried to rescue him but failed. Jiang appeared timely and took Yinniu home. Using the swallow-shaped darts Jiang made several burglaries, hoping to disprove the allegations of Li being "the Swallow". But his trick failed to deceive Lu. Jiang then went to destroy the ammunition warehouse, and asked Yinniu to rescue Li from the prison. Lu and a team of gunmen arrived and fought with Yinniu, who finally killed Lu. Jiang was also slightly injured. Li and Yinniu then fled with him. Soon they all disappeared into the dark.

Starring: Yinniu - Lin Dai Li Debiao - Zhao Lei Jiang Shoushan - Yang Zhiqing Hou Baoshan - He Bin Lu Laoyi - Jiang Nan Dayu - Wang Lan