Shanghai, 1930s: College student Xiang Man is found dead in her dorm. Detective Guan Cen and forensic doctor Ding Eryi investigate, questioning roommate Lu Yizhen and Xiang Man’s boyfriend Zhang Zhiqiang. Clues lead to Professor Fan Kunyi, revealing a shocking connection to the victim.
Lu Yizhen digs deeper into Fan Kunyi’s secret, while a cold case resurfaces. Kidnapping, stolen evidence, and hidden agendas put both her and Guan Cen on edge.
Zhang Zhiqiang is arrested, but old wounds linger. Two years later, Lu Yizhen returns as a police officer, determined to confront the past while keeping her distance from Guan Cen.
Lu Yizhen discovers a missing elderly woman’s body while investigating. At the police station, she gains recognition for her keen observations and works alongside Guan Cen to tackle new mysteries.
A string of deaths linked to elder abuse emerges. Lu Yizhen and Guan Cen face danger when a seemingly helpful neighbor, Fang Ruhai, turns suspicious.
While tracking past offenders, Lu Yizhen learns her family home has been sold to Du Linfeng. A new murder at Taihua Restaurant forces Lu Yizhen and Guan Cen to analyze crime patterns, uncovering disturbing details.
Du Linfeng offers help to Lu Yizhen, revealing his intelligence background. Guan Cen faces scrutiny after a public dispute, while leaks complicate the investigation.
Lu Yizhen clears herself of suspicion in the leak scandal, learning more about the truth behind the crimes. Guan Cen and Ding Eryi work discreetly to maintain control of the investigation.
A series of murders tied to a previous case triggers Lu Yizhen’s lost memories. Guan Cen successfully apprehends a criminal but sacrifices his position, deepening Lu Yizhen’s conflicted feelings toward him.
Old memories resurface as Lu Yizhen investigates past connections. Du Linfeng and Guan Cen provide unexpected support while a new case of a murdered woman in the streets unfolds.
Lu Yizhen and Du Linfeng probe the gambling underworld, while Guan Cen navigates new police responsibilities. An escape and murder at the prison deepen the mystery.
The investigation into school bullying and revenge unfolds. Lu Yizhen races to save her friend Si Min from a vengeful former classmate, with Guan Cen and Du Linfeng intervening just in time.
Lu Yizhen discovers blood evidence in her belongings. Guan Cen and Du Linfeng track shady activities linked to the influential Zhuo family, uncovering a secret meeting.
At a school reunion, Lu Yizhen and Du Linfeng uncover the Zhuo family’s hidden chamber. A confrontation ends with the death of reporter Wu Xiaoxiao, who died protecting Lu Yizhen.
The Zhuo family massacre escalates, leaving investigators racing against time. Lu Yizhen, Guan Cen, and Du Linfeng uncover evidence in a medical clinic, piecing together a human trafficking plot.
Guan Cen and Lu Yizhen face violent attacks during their investigation. Du Linfeng and forensic doctor Gu Sinian work to stabilize injured victims while the trio identifies suspect Tang Jiahao.
Lu Yizhen and Guan Cen thwart a hostage situation while uncovering stolen goods and criminal plans. Confessions and weathered alliances lead to a moment of vulnerability between the two.
A robbery and murder at a pawnshop expose more of the criminal network. Lu Yizhen, Guan Cen, and Du Linfeng use undercover tactics to track suspect Saki.
The team infiltrates a dog farm to eavesdrop on Saki’s plans, discovering his ties to the Zhuo family. Lu Yizhen faces a test of loyalty when asked to prove herself under threat.
Lu Yizhen exposes Saki’s impostor scheme, gaining his cooperation while planning a sting. A tense showdown at the docks nearly backfires, but the team rescues their trapped colleagues.
Suspicions rise as Lu Yizhen and Guan Cen continue probing the “Butcher” operation. Romance begins to blossom amid the high-stakes investigation.
Lu Yizhen revisits her traumatic past to recover lost memories. Guan Cen supports her as clues lead to the elusive Jin Ye, an important key to the case.
Jin Ye meets Tang Jiahao, resulting in a deadly confrontation. Guan Cen and Lu Yizhen race to prevent the Butcher’s next attack, uncovering new leads in time.
The Butcher is finally caught, and long-lost sister Guan Jingning is reunited with Guan Cen. Lu Yizhen accepts Guan Cen’s proposal, while Du Linfeng and Gu Sinian find love, closing the case and their personal arcs.