Anti-drug policeman Liang Dachuan accidentally injured his girlfriend Tang He during a kidnapping incident, and Tang He later died, which made Liang Dachuan heartbroken. Liang Dachuan vowed to solve the case, but Tang He only left a clue - a six-color magic cube. With the help of his colleagues Lv Hanmin, Hang Yulin and Hao Lei, as well as Tang He's sister Tang Lin, Liang Dachuan, with his courage and unyielding spirit, conducted investigations, analysis and reasoning, and used modern criminal investigation methods and superb case-handling wisdom to deal with drug dealers Zhang Dagu, Lu Jihong and others, and finally cracked the mystery carefully set by the drug cartel, and finally captured the drug lord Flamingo Tong Feng, restoring peace to the society.