Zhang Lei (Sun Honglei), the captain of the Jinhai City Anti-drug Brigade, who had just finished a dangerous mission, accidentally met Cai Tianming (Louis Koo), a Hong Konger who was hospitalized for a car accident. The battle-hardened Zhang quickly determined that Cai was related to drug trafficking. Through the interrogation of Cai, it was learned that a truck of methamphetamine from Yuejiang arrived in Jinhai that day and was about to trade with the local drug dealer Haha, and Cai was the middleman between the two parties. In order to save his life, Cai Tianming actively cooperated and assisted Zhang to disguise himself as the nephew of Li Zhenbiao, a well-known drug lord in Yuejiang, to meet Haha. Then the anti-drug brigade went all the way south, passing by Cai's drug processing factory in Ezhou, and finally arrived in Yuejiang to trade with Li Zhenbiao. Dealing with cunning and fierce criminals, even the experienced Zhang must be cautious and deal with them step by step. After a dangerous test, the two sides finally ushered in the last moment of the transaction, but at this time, this chess game full of murderous intentions was completely out of control...