Police detective Jiang Linfeng was born into a poor family. Through exceptional talent and relentless hard work, he became the youngest trace evidence expert at the public security bureau of a provincial capital in southern China. Recommended by his mentor, Dong Zhengran of the municipal criminal investigation bureau, he joined the Ministry of Public Security's Center for Forensic Science, where he studied under the renowned expert Hu Shouyi. His outstanding expertise earned him a place on the South China Provincial Expert Team for Unsolved Homicide Cases, where he fought alongside elite investigators from across the region: the frank and hearty Sister Fang from Guangcheng, the sharp and perceptive young Jin Xiaoshuang, the steady and dependable Lin Chuan from Focheng, the selfless and fiercely protective Zhao Wanhua, the poised and elegant Sun Yuhua from Zhucheng, the brave and resilient Qian Fengyi from Huadu, and the respected provincial department veteran Chang Yuanda. Working together, the team reopened seventeen long-forgotten cold cases, using fingerprints as keys to reveal the tangled humanity hidden behind the evidence. Every incomplete fingerprint is a silent confession, and he and his team are the ones who see the dead through to the end of their final journey.