"Detective" tells the story of the protagonist Dae-man (Kwon Sang-woo), who has a genius sixth sense for investigation, and the veteran detective (Sung Dong-il) who solve a mysterious murder case together. Dae-man, played by Kwon Sang-woo, is the head of a family and runs a comic book store to make a living. In private, he is actually a genius detective who runs a club and blog for domestic unsolved cases and crime analysis. This is also Kwon Sang-woo's return to the Korean big screen since "Pain" in 2011. Seo Young-hee plays a wife with strong living ability in the film. The cooperation between Kwon Sang-woo and Seo Young-hee is also very much anticipated by fans.