Nazotoki wa Dinner no Ato de

 is a Japanese television drama series based on the mystery novel of the same name by Japanese author Tokuya Higashigawa. It premiered on Fuji TV on October 18, 2011. This drama series was subsequently followed two-hour long special episode, then a film sequel.
Plot.
Reiko is a rich heiress to a zaibatsu, but she chose to work as a detective. She resents her superior, Kazamatsuri, who always seem to be making illogical deductions that causes murder cases to become cold cases. One day, her butler suddenly announces his retirement, and he chooses Kageyama as his replacement. Reiko realizes that Kageyama's deduction skills are very good after Kageyama solved a seemingly unsolvable mystery. After that, whenever Reiko meets an unsolvable case, she would lay out the details of the case for Kageyama, and he would explain to her how that particular case is solved after dinner. After every case, Kageyama also explains to Reikko some universal truth or human nature that led to each crime being committed.