Three years ago, due to the intelligence error of criminal police Liu Yuanwen, his fiancée, the newly promoted criminal police Rong Yu, died in the fire scene of the drug dealers. Criminal police Rong Yao of the anti-drug brigade turned against his good brother Liu Yuanwen because of the death of his sister. Liu Yuanwen left the police station in despair and disappeared. In order to take revenge, Rong Yao became the captain of the Yungang City Anti-drug Brigade after three years of continuous efforts. In order to destroy the drug trafficking K group and dig out the leader of the international drug trafficking organization "Ghost", the Municipal Public Security Bureau drew resources to set up the "84 Group". Rong Yao resolutely took over the position of team leader for revenge, but unexpectedly, the first task of the group was to provide support for Liu Yuanwen, the only remaining undercover in the "K" group, to help him get promoted and contact the core of the K organization. Therefore, the ruthless reality made the two people who were tortured by fate choose to cooperate again. As they approached the truth step by step, they found that Rong Yu might still be alive.