This is a story taking place in Shanghai in the 1940s. No. 108, Caoxiewan Road was where the famous private detective Sha Qiuke worked and lived with his son Sha Xiaoqiu. As Sha Xiaoqiu grew older, his exceptional powers of observation and deduction became evident, and he even starts providing advice for his father, the great detective Sha Qiuke. When Sha Xiaoqiu was ten, Sha Qiuke took over a trafficking case which was quite complex and thorny. After the so many twists and turns, a key breakthrough was achieved. But just when Sha Qiuke and Sha Xiaoqiu were about to take the next step, an unexpected thing happened...