Detective Chang San: Dawn Killer

On the 221 train bound for City S, Binhai City real estate tycoon Zhou Fuyuan was suddenly found dead in his seat at dawn. His adopted daughter and second son are suspected by the police as the biggest suspects. During a search of the bedroom of Zhou Fuyuan's home, the police discovered photos and remittance orders of a mysterious woman. Zhou Fuyuan had been sending money to her for decades, but no one in the Zhou family knew who this woman was. Zhou Fuyuan's adopted daughter was also killed a month later. The time of death was surprisingly consistent with Zhou Fuyuan's death time, and his second son also mysteriously disappeared.