Lin Yan, a cold and arrogant female forensic expert, meets Song Yuhang, a righteous and sharp female detective. From being incompatible to becoming friends, they witness the lives of many ordinary people along the way: a young girl who struggles to survive but dies innocently, an old mother who waits for her criminal son to return in the mountains, a timid policeman who faces a gun-wielding robber bravely... They fight for the rights of the living, speak for the dead, and vow to uncover the truth that has been silent for years.