Genius swindler Otowa No. 4 (Hayami Mokomichi : Absolute Boyfriend , Forever w. you , Oh! My Girl ,   Kochikame ) is finally arrested but escapes with Azabu No. 10 from a paddy wagon while being transported to the police station. The two men then hides at the nearby Hikari Gakuen High School. Hikari Gakuen principle Kenichi Mizuki (Kohinata Fumiyo) finds Owowa and offers him an unusual deal. The principle will harbor the fugitive if Otowa takes the identity of teacher Goro Hachisuka - a new teacher who graduated from Tokyo University. Otowa must now teach the most problematic students in lessons known as "hammer sessions". Every week a new trouble student appears and it is up to Goro Hachisuka to solve their problems.