1. "Flowers bloom and the moon is full that year": The play is set in the Republic of China and tells the story of the struggle and love between a red female agent and a gang leader.
2. Autumn Water: This drama is set in Shanghai in 1930s and 1950s, depicting the struggle between gangs and police, and also showing the style and social phenomena of that era.
3. The city that never sleeps: The play is set in a modern city, which describes the confrontation between a police who insists on justice and gang forces and reveals the contest between crime and power.
4. True colors of Interpol: This drama is one of the representative works of Hong Kong TV series. By describing the struggle between Interpol and criminals, it shows the dark side of Hong Kong society and the efforts of the police.
5. "Detective De Renjie": The play is based on the accidental events in the Tang Dynasty, and depicts the detection process of De Renjie, which is full of suspense and reasoning elements.
Please note that the above are some classic TV dramas recommended by the police.