Four detectives specialize in reopening cold cases. Their limits are put to the test in the face of brutal truths and twisted humanity. Luo Ying Wei is the talkative team lead of three young detectives in Pingling City. Cai Wen Xin is known as the queen of gossip, Xia Luo Yang is beautiful and determined while Feng Yi brings up the rear as the quiet and bookish member of the group. Bringing the four ladies together is like a disaster waiting to happen, yet they manage to prove themselves time and again. With the help of Cai Wen Xin's older brother Cai Wen Fei and under the guidance of their superiors in the police force, this small team of four work together in each case and ultimately go head to head with a massive drug syndicate.

• Li Yuan
• Shi Shi
• Wang Yu
• Chen Muyang
• Pu Tao
• Cheng Yu
• Yang Xinming
• Li Chengru