He Wansheng (Kwon Sang-woo) is an ace detective. He has a perfect appearance like a sculpture, but he believes in intuition more than reasoning, and fists more than the law. He doesn't like complicated processes, and relies on animal instincts and sharp intuition to catch criminals. Liu Xueyu (Choi Kang-hee) uses knowledge and experience as the basis to conduct complex reasoning to find the truth. The two have completely opposite ways of doing things, but together they are a dream partner. The two work together to investigate various criminal incidents.