Late one night, in the old town of a coastal city, a mysterious murder took place. Guan Jingtang, a locally well-known and respected elder, was brutally killed in his villa. Detective Captain An Ping was urgently assigned to the case, while Shang Jie, a top graduate from the provincial police academy, volunteered to assist. The two worked together closely, conducting a meticulous investigation. However, as they delved deeper, they encountered numerous contradictory clues, along with a missing large sum of cash, a familiar woman in a red dress, blood-red floral patterns, and the complex relationships within the Guan family, all of which made the case increasingly baffling. To make matters worse, more murders followed, with the victims all having close ties to Guan Jingtang. Under immense pressure, An Ping and Shang Jie began investigating from the very beginning, uncovering an old, unresolved case. It turns out that An Ping's mentor, who was also Shang Jie's father, had died because of that very case. Eventually, An Ping painstakingly pieced together the truth, unmasking the twisted mind behind the crimes and bringing the culprit to justice. Shang Jie, too, overcame the shadows of her past, resolving long-standing personal conflicts. She decided to continue on her father's legacy and fight alongside An Ping.