Lucheng was poisoned by Ge Yun with barbiturates and committed suicide by fabricating the scene as a love affair.

Lu Cheng didn't come to work for a long time. Han Yundong sent someone to find him, only to find that he was dead. Chen Dongsheng, Pang Hongmei and others came to Lu Cheng's home to investigate and found a suicide note on the table, suspecting that he committed suicide for love.

Bai Hui did not believe that Lu Cheng would commit suicide. She accidentally saw a bottle of poison in Ge Yun's bag and suspected that Ge Yun had killed Lu Cheng. She came to Ge Yun to argue, and Ge Yun admitted that she had killed Lu Cheng, and that she had killed Lu Cheng.Before Bai Hui, because Lu Cheng finally discovered Bai Hui's true identity and knew that she was a spy, those sweet words before were just a way to deceive him.

Ge Yun took out the report letter written by Lu Cheng and burned it on the spot.The reason why Ge Yun killed him was because she was not a good person. She was a secret agent who had been lurking in the police station.